libavcodec/mjpegdec.c
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00001 /*
00002  * MJPEG decoder
00003  * Copyright (c) 2000, 2001 Fabrice Bellard
00004  * Copyright (c) 2003 Alex Beregszaszi
00005  * Copyright (c) 2003-2004 Michael Niedermayer
00006  *
00007  * Support for external huffman table, various fixes (AVID workaround),
00008  * aspecting, new decode_frame mechanism and apple mjpeg-b support
00009  *                                  by Alex Beregszaszi
00010  *
00011  * This file is part of Libav.
00012  *
00013  * Libav is free software; you can redistribute it and/or
00014  * modify it under the terms of the GNU Lesser General Public
00015  * License as published by the Free Software Foundation; either
00016  * version 2.1 of the License, or (at your option) any later version.
00017  *
00018  * Libav is distributed in the hope that it will be useful,
00019  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00020  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00021  * Lesser General Public License for more details.
00022  *
00023  * You should have received a copy of the GNU Lesser General Public
00024  * License along with Libav; if not, write to the Free Software
00025  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00026  */
00027 
00033 // #define DEBUG
00034 #include <assert.h>
00035 
00036 #include "libavutil/imgutils.h"
00037 #include "libavutil/opt.h"
00038 #include "avcodec.h"
00039 #include "dsputil.h"
00040 #include "mjpeg.h"
00041 #include "mjpegdec.h"
00042 #include "jpeglsdec.h"
00043 
00044 
00045 static int build_vlc(VLC *vlc, const uint8_t *bits_table,
00046                      const uint8_t *val_table, int nb_codes,
00047                      int use_static, int is_ac)
00048 {
00049     uint8_t huff_size[256];
00050     uint16_t huff_code[256];
00051     uint16_t huff_sym[256];
00052     int i;
00053 
00054     assert(nb_codes <= 256);
00055 
00056     memset(huff_size, 0, sizeof(huff_size));
00057     ff_mjpeg_build_huffman_codes(huff_size, huff_code, bits_table, val_table);
00058 
00059     for (i = 0; i < 256; i++)
00060         huff_sym[i] = i + 16 * is_ac;
00061 
00062     if (is_ac)
00063         huff_sym[0] = 16 * 256;
00064 
00065     return ff_init_vlc_sparse(vlc, 9, nb_codes, huff_size, 1, 1,
00066                               huff_code, 2, 2, huff_sym, 2, 2, use_static);
00067 }
00068 
00069 static void build_basic_mjpeg_vlc(MJpegDecodeContext *s)
00070 {
00071     build_vlc(&s->vlcs[0][0], ff_mjpeg_bits_dc_luminance,
00072               ff_mjpeg_val_dc, 12, 0, 0);
00073     build_vlc(&s->vlcs[0][1], ff_mjpeg_bits_dc_chrominance,
00074               ff_mjpeg_val_dc, 12, 0, 0);
00075     build_vlc(&s->vlcs[1][0], ff_mjpeg_bits_ac_luminance,
00076               ff_mjpeg_val_ac_luminance, 251, 0, 1);
00077     build_vlc(&s->vlcs[1][1], ff_mjpeg_bits_ac_chrominance,
00078               ff_mjpeg_val_ac_chrominance, 251, 0, 1);
00079     build_vlc(&s->vlcs[2][0], ff_mjpeg_bits_ac_luminance,
00080               ff_mjpeg_val_ac_luminance, 251, 0, 0);
00081     build_vlc(&s->vlcs[2][1], ff_mjpeg_bits_ac_chrominance,
00082               ff_mjpeg_val_ac_chrominance, 251, 0, 0);
00083 }
00084 
00085 av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)
00086 {
00087     MJpegDecodeContext *s = avctx->priv_data;
00088 
00089     if (!s->picture_ptr)
00090         s->picture_ptr = &s->picture;
00091 
00092     s->avctx = avctx;
00093     dsputil_init(&s->dsp, avctx);
00094     ff_init_scantable(s->dsp.idct_permutation, &s->scantable, ff_zigzag_direct);
00095     s->buffer_size   = 0;
00096     s->buffer        = NULL;
00097     s->start_code    = -1;
00098     s->first_picture = 1;
00099     s->org_height    = avctx->coded_height;
00100     avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
00101 
00102     build_basic_mjpeg_vlc(s);
00103 
00104 #if FF_API_MJPEG_GLOBAL_OPTS
00105     if (avctx->flags & CODEC_FLAG_EXTERN_HUFF)
00106         s->extern_huff = 1;
00107 #endif
00108     if (s->extern_huff) {
00109         av_log(avctx, AV_LOG_INFO, "mjpeg: using external huffman table\n");
00110         init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size * 8);
00111         if (ff_mjpeg_decode_dht(s)) {
00112             av_log(avctx, AV_LOG_ERROR,
00113                    "mjpeg: error using external huffman table\n");
00114             return AVERROR_INVALIDDATA;
00115         }
00116     }
00117     if (avctx->field_order == AV_FIELD_BB) { /* quicktime icefloe 019 */
00118         s->interlace_polarity = 1;           /* bottom field first */
00119         av_log(avctx, AV_LOG_DEBUG, "mjpeg bottom field first\n");
00120     }
00121     if (avctx->codec->id == CODEC_ID_AMV)
00122         s->flipped = 1;
00123 
00124     return 0;
00125 }
00126 
00127 
00128 /* quantize tables */
00129 int ff_mjpeg_decode_dqt(MJpegDecodeContext *s)
00130 {
00131     int len, index, i, j;
00132 
00133     len = get_bits(&s->gb, 16) - 2;
00134 
00135     while (len >= 65) {
00136         /* only 8 bit precision handled */
00137         if (get_bits(&s->gb, 4) != 0) {
00138             av_log(s->avctx, AV_LOG_ERROR, "dqt: 16bit precision\n");
00139             return -1;
00140         }
00141         index = get_bits(&s->gb, 4);
00142         if (index >= 4)
00143             return -1;
00144         av_log(s->avctx, AV_LOG_DEBUG, "index=%d\n", index);
00145         /* read quant table */
00146         for (i = 0; i < 64; i++) {
00147             j = s->scantable.permutated[i];
00148             s->quant_matrixes[index][j] = get_bits(&s->gb, 8);
00149         }
00150 
00151         // XXX FIXME finetune, and perhaps add dc too
00152         s->qscale[index] = FFMAX(s->quant_matrixes[index][s->scantable.permutated[1]],
00153                                  s->quant_matrixes[index][s->scantable.permutated[8]]) >> 1;
00154         av_log(s->avctx, AV_LOG_DEBUG, "qscale[%d]: %d\n",
00155                index, s->qscale[index]);
00156         len -= 65;
00157     }
00158     return 0;
00159 }
00160 
00161 /* decode huffman tables and build VLC decoders */
00162 int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
00163 {
00164     int len, index, i, class, n, v, code_max;
00165     uint8_t bits_table[17];
00166     uint8_t val_table[256];
00167 
00168     len = get_bits(&s->gb, 16) - 2;
00169 
00170     while (len > 0) {
00171         if (len < 17)
00172             return -1;
00173         class = get_bits(&s->gb, 4);
00174         if (class >= 2)
00175             return -1;
00176         index = get_bits(&s->gb, 4);
00177         if (index >= 4)
00178             return -1;
00179         n = 0;
00180         for (i = 1; i <= 16; i++) {
00181             bits_table[i] = get_bits(&s->gb, 8);
00182             n += bits_table[i];
00183         }
00184         len -= 17;
00185         if (len < n || n > 256)
00186             return -1;
00187 
00188         code_max = 0;
00189         for (i = 0; i < n; i++) {
00190             v = get_bits(&s->gb, 8);
00191             if (v > code_max)
00192                 code_max = v;
00193             val_table[i] = v;
00194         }
00195         len -= n;
00196 
00197         /* build VLC and flush previous vlc if present */
00198         ff_free_vlc(&s->vlcs[class][index]);
00199         av_log(s->avctx, AV_LOG_DEBUG, "class=%d index=%d nb_codes=%d\n",
00200                class, index, code_max + 1);
00201         if (build_vlc(&s->vlcs[class][index], bits_table, val_table,
00202                       code_max + 1, 0, class > 0) < 0)
00203             return -1;
00204 
00205         if (class > 0) {
00206             ff_free_vlc(&s->vlcs[2][index]);
00207             if (build_vlc(&s->vlcs[2][index], bits_table, val_table,
00208                           code_max + 1, 0, 0) < 0)
00209                 return -1;
00210         }
00211     }
00212     return 0;
00213 }
00214 
00215 int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
00216 {
00217     int len, nb_components, i, width, height, pix_fmt_id;
00218 
00219     /* XXX: verify len field validity */
00220     len     = get_bits(&s->gb, 16);
00221     s->bits = get_bits(&s->gb, 8);
00222 
00223     if (s->pegasus_rct)
00224         s->bits = 9;
00225     if (s->bits == 9 && !s->pegasus_rct)
00226         s->rct  = 1;    // FIXME ugly
00227 
00228     if (s->bits != 8 && !s->lossless) {
00229         av_log(s->avctx, AV_LOG_ERROR, "only 8 bits/component accepted\n");
00230         return -1;
00231     }
00232 
00233     height = get_bits(&s->gb, 16);
00234     width  = get_bits(&s->gb, 16);
00235 
00236     // HACK for odd_height.mov
00237     if (s->interlaced && s->width == width && s->height == height + 1)
00238         height= s->height;
00239 
00240     av_log(s->avctx, AV_LOG_DEBUG, "sof0: picture: %dx%d\n", width, height);
00241     if (av_image_check_size(width, height, 0, s->avctx))
00242         return -1;
00243 
00244     nb_components = get_bits(&s->gb, 8);
00245     if (nb_components <= 0 ||
00246         nb_components > MAX_COMPONENTS)
00247         return -1;
00248     if (s->ls && !(s->bits <= 8 || nb_components == 1)) {
00249         av_log(s->avctx, AV_LOG_ERROR,
00250                "only <= 8 bits/component or 16-bit gray accepted for JPEG-LS\n");
00251         return -1;
00252     }
00253     s->nb_components = nb_components;
00254     s->h_max         = 1;
00255     s->v_max         = 1;
00256     for (i = 0; i < nb_components; i++) {
00257         /* component id */
00258         s->component_id[i] = get_bits(&s->gb, 8) - 1;
00259         s->h_count[i]      = get_bits(&s->gb, 4);
00260         s->v_count[i]      = get_bits(&s->gb, 4);
00261         /* compute hmax and vmax (only used in interleaved case) */
00262         if (s->h_count[i] > s->h_max)
00263             s->h_max = s->h_count[i];
00264         if (s->v_count[i] > s->v_max)
00265             s->v_max = s->v_count[i];
00266         s->quant_index[i] = get_bits(&s->gb, 8);
00267         if (s->quant_index[i] >= 4)
00268             return -1;
00269         av_log(s->avctx, AV_LOG_DEBUG, "component %d %d:%d id: %d quant:%d\n",
00270                i, s->h_count[i], s->v_count[i],
00271                s->component_id[i], s->quant_index[i]);
00272     }
00273 
00274     if (s->ls && (s->h_max > 1 || s->v_max > 1)) {
00275         av_log(s->avctx, AV_LOG_ERROR,
00276                "Subsampling in JPEG-LS is not supported.\n");
00277         return -1;
00278     }
00279 
00280     if (s->v_max == 1 && s->h_max == 1 && s->lossless == 1)
00281         s->rgb = 1;
00282 
00283     /* if different size, realloc/alloc picture */
00284     /* XXX: also check h_count and v_count */
00285     if (width != s->width || height != s->height) {
00286         av_freep(&s->qscale_table);
00287 
00288         s->width      = width;
00289         s->height     = height;
00290         s->interlaced = 0;
00291 
00292         /* test interlaced mode */
00293         if (s->first_picture   &&
00294             s->org_height != 0 &&
00295             s->height < ((s->org_height * 3) / 4)) {
00296             s->interlaced                    = 1;
00297             s->bottom_field                  = s->interlace_polarity;
00298             s->picture_ptr->interlaced_frame = 1;
00299             s->picture_ptr->top_field_first  = !s->interlace_polarity;
00300             height *= 2;
00301         }
00302 
00303         avcodec_set_dimensions(s->avctx, width, height);
00304 
00305         s->qscale_table  = av_mallocz((s->width + 15) / 16);
00306         s->first_picture = 0;
00307     }
00308 
00309     if (!(s->interlaced && (s->bottom_field == !s->interlace_polarity))) {
00310     /* XXX: not complete test ! */
00311     pix_fmt_id = (s->h_count[0] << 28) | (s->v_count[0] << 24) |
00312                  (s->h_count[1] << 20) | (s->v_count[1] << 16) |
00313                  (s->h_count[2] << 12) | (s->v_count[2] <<  8) |
00314                  (s->h_count[3] <<  4) |  s->v_count[3];
00315     av_log(s->avctx, AV_LOG_DEBUG, "pix fmt id %x\n", pix_fmt_id);
00316     /* NOTE we do not allocate pictures large enough for the possible
00317      * padding of h/v_count being 4 */
00318     if (!(pix_fmt_id & 0xD0D0D0D0))
00319         pix_fmt_id -= (pix_fmt_id & 0xF0F0F0F0) >> 1;
00320     if (!(pix_fmt_id & 0x0D0D0D0D))
00321         pix_fmt_id -= (pix_fmt_id & 0x0F0F0F0F) >> 1;
00322 
00323     switch (pix_fmt_id) {
00324     case 0x11111100:
00325         if (s->rgb)
00326             s->avctx->pix_fmt = PIX_FMT_BGRA;
00327         else
00328             s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV444P : PIX_FMT_YUVJ444P;
00329         assert(s->nb_components == 3);
00330         break;
00331     case 0x11000000:
00332         s->avctx->pix_fmt = PIX_FMT_GRAY8;
00333         break;
00334     case 0x12111100:
00335         s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV440P : PIX_FMT_YUVJ440P;
00336         break;
00337     case 0x21111100:
00338         s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV422P : PIX_FMT_YUVJ422P;
00339         break;
00340     case 0x22111100:
00341         s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV420P : PIX_FMT_YUVJ420P;
00342         break;
00343     default:
00344         av_log(s->avctx, AV_LOG_ERROR, "Unhandled pixel format 0x%x\n", pix_fmt_id);
00345         return -1;
00346     }
00347     if (s->ls) {
00348         if (s->nb_components > 1)
00349             s->avctx->pix_fmt = PIX_FMT_RGB24;
00350         else if (s->bits <= 8)
00351             s->avctx->pix_fmt = PIX_FMT_GRAY8;
00352         else
00353             s->avctx->pix_fmt = PIX_FMT_GRAY16;
00354     }
00355 
00356     if (s->picture_ptr->data[0])
00357         s->avctx->release_buffer(s->avctx, s->picture_ptr);
00358 
00359     if (s->avctx->get_buffer(s->avctx, s->picture_ptr) < 0) {
00360         av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00361         return -1;
00362     }
00363     s->picture_ptr->pict_type = AV_PICTURE_TYPE_I;
00364     s->picture_ptr->key_frame = 1;
00365     s->got_picture            = 1;
00366 
00367     for (i = 0; i < 3; i++)
00368         s->linesize[i] = s->picture_ptr->linesize[i] << s->interlaced;
00369 
00370 //    printf("%d %d %d %d %d %d\n",
00371 //           s->width, s->height, s->linesize[0], s->linesize[1],
00372 //           s->interlaced, s->avctx->height);
00373 
00374     if (len != (8 + (3 * nb_components)))
00375         av_log(s->avctx, AV_LOG_DEBUG, "decode_sof0: error, len(%d) mismatch\n", len);
00376     }
00377 
00378     /* totally blank picture as progressive JPEG will only add details to it */
00379     if (s->progressive) {
00380         int bw = (width  + s->h_max * 8 - 1) / (s->h_max * 8);
00381         int bh = (height + s->v_max * 8 - 1) / (s->v_max * 8);
00382         for (i = 0; i < s->nb_components; i++) {
00383             int size = bw * bh * s->h_count[i] * s->v_count[i];
00384             av_freep(&s->blocks[i]);
00385             av_freep(&s->last_nnz[i]);
00386             s->blocks[i]       = av_malloc(size * sizeof(**s->blocks));
00387             s->last_nnz[i]     = av_mallocz(size * sizeof(**s->last_nnz));
00388             s->block_stride[i] = bw * s->h_count[i];
00389         }
00390         memset(s->coefs_finished, 0, sizeof(s->coefs_finished));
00391     }
00392     return 0;
00393 }
00394 
00395 static inline int mjpeg_decode_dc(MJpegDecodeContext *s, int dc_index)
00396 {
00397     int code;
00398     code = get_vlc2(&s->gb, s->vlcs[0][dc_index].table, 9, 2);
00399     if (code < 0) {
00400         av_log(s->avctx, AV_LOG_WARNING,
00401                "mjpeg_decode_dc: bad vlc: %d:%d (%p)\n",
00402                0, dc_index, &s->vlcs[0][dc_index]);
00403         return 0xffff;
00404     }
00405 
00406     if (code)
00407         return get_xbits(&s->gb, code);
00408     else
00409         return 0;
00410 }
00411 
00412 /* decode block and dequantize */
00413 static int decode_block(MJpegDecodeContext *s, DCTELEM *block, int component,
00414                         int dc_index, int ac_index, int16_t *quant_matrix)
00415 {
00416     int code, i, j, level, val;
00417 
00418     /* DC coef */
00419     val = mjpeg_decode_dc(s, dc_index);
00420     if (val == 0xffff) {
00421         av_log(s->avctx, AV_LOG_ERROR, "error dc\n");
00422         return -1;
00423     }
00424     val = val * quant_matrix[0] + s->last_dc[component];
00425     s->last_dc[component] = val;
00426     block[0] = val;
00427     /* AC coefs */
00428     i = 0;
00429     {OPEN_READER(re, &s->gb);
00430     do {
00431         UPDATE_CACHE(re, &s->gb);
00432         GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2);
00433 
00434         i += ((unsigned)code) >> 4;
00435             code &= 0xf;
00436         if (code) {
00437             if (code > MIN_CACHE_BITS - 16)
00438                 UPDATE_CACHE(re, &s->gb);
00439 
00440             {
00441                 int cache = GET_CACHE(re, &s->gb);
00442                 int sign  = (~cache) >> 31;
00443                 level     = (NEG_USR32(sign ^ cache,code) ^ sign) - sign;
00444             }
00445 
00446             LAST_SKIP_BITS(re, &s->gb, code);
00447 
00448             if (i > 63) {
00449                 av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);
00450                 return -1;
00451             }
00452             j        = s->scantable.permutated[i];
00453             block[j] = level * quant_matrix[j];
00454         }
00455     } while (i < 63);
00456     CLOSE_READER(re, &s->gb);}
00457 
00458     return 0;
00459 }
00460 
00461 static int decode_dc_progressive(MJpegDecodeContext *s, DCTELEM *block,
00462                                  int component, int dc_index,
00463                                  int16_t *quant_matrix, int Al)
00464 {
00465     int val;
00466     s->dsp.clear_block(block);
00467     val = mjpeg_decode_dc(s, dc_index);
00468     if (val == 0xffff) {
00469         av_log(s->avctx, AV_LOG_ERROR, "error dc\n");
00470         return -1;
00471     }
00472     val = (val * quant_matrix[0] << Al) + s->last_dc[component];
00473     s->last_dc[component] = val;
00474     block[0] = val;
00475     return 0;
00476 }
00477 
00478 /* decode block and dequantize - progressive JPEG version */
00479 static int decode_block_progressive(MJpegDecodeContext *s, DCTELEM *block,
00480                                     uint8_t *last_nnz, int ac_index,
00481                                     int16_t *quant_matrix,
00482                                     int ss, int se, int Al, int *EOBRUN)
00483 {
00484     int code, i, j, level, val, run;
00485 
00486     if (*EOBRUN) {
00487         (*EOBRUN)--;
00488         return 0;
00489     }
00490 
00491     {
00492         OPEN_READER(re, &s->gb);
00493         for (i = ss; ; i++) {
00494             UPDATE_CACHE(re, &s->gb);
00495             GET_VLC(code, re, &s->gb, s->vlcs[2][ac_index].table, 9, 2);
00496 
00497             run = ((unsigned) code) >> 4;
00498             code &= 0xF;
00499             if (code) {
00500                 i += run;
00501                 if (code > MIN_CACHE_BITS - 16)
00502                     UPDATE_CACHE(re, &s->gb);
00503 
00504                 {
00505                     int cache = GET_CACHE(re, &s->gb);
00506                     int sign  = (~cache) >> 31;
00507                     level     = (NEG_USR32(sign ^ cache,code) ^ sign) - sign;
00508                 }
00509 
00510                 LAST_SKIP_BITS(re, &s->gb, code);
00511 
00512                 if (i >= se) {
00513                     if (i == se) {
00514                         j = s->scantable.permutated[se];
00515                         block[j] = level * quant_matrix[j] << Al;
00516                         break;
00517                     }
00518                     av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);
00519                     return -1;
00520                 }
00521                 j = s->scantable.permutated[i];
00522                 block[j] = level * quant_matrix[j] << Al;
00523             } else {
00524                 if (run == 0xF) {// ZRL - skip 15 coefficients
00525                     i += 15;
00526                     if (i >= se) {
00527                         av_log(s->avctx, AV_LOG_ERROR, "ZRL overflow: %d\n", i);
00528                         return -1;
00529                     }
00530                 } else {
00531                     val = (1 << run);
00532                     if (run) {
00533                         UPDATE_CACHE(re, &s->gb);
00534                         val += NEG_USR32(GET_CACHE(re, &s->gb), run);
00535                         LAST_SKIP_BITS(re, &s->gb, run);
00536                     }
00537                     *EOBRUN = val - 1;
00538                     break;
00539                 }
00540             }
00541         }
00542         CLOSE_READER(re, &s->gb);
00543     }
00544 
00545     if (i > *last_nnz)
00546         *last_nnz = i;
00547 
00548     return 0;
00549 }
00550 
00551 #define REFINE_BIT(j) {                                             \
00552     UPDATE_CACHE(re, &s->gb);                                       \
00553     sign = block[j] >> 15;                                          \
00554     block[j] += SHOW_UBITS(re, &s->gb, 1) *                         \
00555                 ((quant_matrix[j] ^ sign) - sign) << Al;            \
00556     LAST_SKIP_BITS(re, &s->gb, 1);                                  \
00557 }
00558 
00559 #define ZERO_RUN                                                    \
00560 for (; ; i++) {                                                     \
00561     if (i > last) {                                                 \
00562         i += run;                                                   \
00563         if (i > se) {                                               \
00564             av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i); \
00565             return -1;                                              \
00566         }                                                           \
00567         break;                                                      \
00568     }                                                               \
00569     j = s->scantable.permutated[i];                                 \
00570     if (block[j])                                                   \
00571         REFINE_BIT(j)                                               \
00572     else if (run-- == 0)                                            \
00573         break;                                                      \
00574 }
00575 
00576 /* decode block and dequantize - progressive JPEG refinement pass */
00577 static int decode_block_refinement(MJpegDecodeContext *s, DCTELEM *block,
00578                                    uint8_t *last_nnz,
00579                                    int ac_index, int16_t *quant_matrix,
00580                                    int ss, int se, int Al, int *EOBRUN)
00581 {
00582     int code, i = ss, j, sign, val, run;
00583     int last    = FFMIN(se, *last_nnz);
00584 
00585     OPEN_READER(re, &s->gb);
00586     if (*EOBRUN) {
00587         (*EOBRUN)--;
00588     } else {
00589         for (; ; i++) {
00590             UPDATE_CACHE(re, &s->gb);
00591             GET_VLC(code, re, &s->gb, s->vlcs[2][ac_index].table, 9, 2);
00592 
00593             if (code & 0xF) {
00594                 run = ((unsigned) code) >> 4;
00595                 UPDATE_CACHE(re, &s->gb);
00596                 val = SHOW_UBITS(re, &s->gb, 1);
00597                 LAST_SKIP_BITS(re, &s->gb, 1);
00598                 ZERO_RUN;
00599                 j = s->scantable.permutated[i];
00600                 val--;
00601                 block[j] = ((quant_matrix[j]^val) - val) << Al;
00602                 if (i == se) {
00603                     if (i > *last_nnz)
00604                         *last_nnz = i;
00605                     CLOSE_READER(re, &s->gb);
00606                     return 0;
00607                 }
00608             } else {
00609                 run = ((unsigned) code) >> 4;
00610                 if (run == 0xF) {
00611                     ZERO_RUN;
00612                 } else {
00613                     val = run;
00614                     run = (1 << run);
00615                     if (val) {
00616                         UPDATE_CACHE(re, &s->gb);
00617                         run += SHOW_UBITS(re, &s->gb, val);
00618                         LAST_SKIP_BITS(re, &s->gb, val);
00619                     }
00620                     *EOBRUN = run - 1;
00621                     break;
00622                 }
00623             }
00624         }
00625 
00626         if (i > *last_nnz)
00627             *last_nnz = i;
00628     }
00629 
00630     for (; i <= last; i++) {
00631         j = s->scantable.permutated[i];
00632         if (block[j])
00633             REFINE_BIT(j)
00634     }
00635     CLOSE_READER(re, &s->gb);
00636 
00637     return 0;
00638 }
00639 #undef REFINE_BIT
00640 #undef ZERO_RUN
00641 
00642 static int ljpeg_decode_rgb_scan(MJpegDecodeContext *s, int predictor,
00643                                  int point_transform)
00644 {
00645     int i, mb_x, mb_y;
00646     uint16_t (*buffer)[4];
00647     int left[3], top[3], topleft[3];
00648     const int linesize = s->linesize[0];
00649     const int mask     = (1 << s->bits) - 1;
00650 
00651     av_fast_malloc(&s->ljpeg_buffer, &s->ljpeg_buffer_size,
00652                    (unsigned)s->mb_width * 4 * sizeof(s->ljpeg_buffer[0][0]));
00653     buffer = s->ljpeg_buffer;
00654 
00655     for (i = 0; i < 3; i++)
00656         buffer[0][i] = 1 << (s->bits + point_transform - 1);
00657 
00658     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
00659         const int modified_predictor = mb_y ? predictor : 1;
00660         uint8_t *ptr = s->picture_ptr->data[0] + (linesize * mb_y);
00661 
00662         if (s->interlaced && s->bottom_field)
00663             ptr += linesize >> 1;
00664 
00665         for (i = 0; i < 3; i++)
00666             top[i] = left[i] = topleft[i] = buffer[0][i];
00667 
00668         for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
00669             if (s->restart_interval && !s->restart_count)
00670                 s->restart_count = s->restart_interval;
00671 
00672             for (i = 0; i < 3; i++) {
00673                 int pred;
00674 
00675                 topleft[i] = top[i];
00676                 top[i]     = buffer[mb_x][i];
00677 
00678                 PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
00679 
00680                 left[i] = buffer[mb_x][i] =
00681                     mask & (pred + (mjpeg_decode_dc(s, s->dc_index[i]) << point_transform));
00682             }
00683 
00684             if (s->restart_interval && !--s->restart_count) {
00685                 align_get_bits(&s->gb);
00686                 skip_bits(&s->gb, 16); /* skip RSTn */
00687             }
00688         }
00689 
00690         if (s->rct) {
00691             for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
00692                 ptr[4 * mb_x + 1] = buffer[mb_x][0] - ((buffer[mb_x][1] + buffer[mb_x][2] - 0x200) >> 2);
00693                 ptr[4 * mb_x + 0] = buffer[mb_x][1] + ptr[4 * mb_x + 1];
00694                 ptr[4 * mb_x + 2] = buffer[mb_x][2] + ptr[4 * mb_x + 1];
00695             }
00696         } else if (s->pegasus_rct) {
00697             for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
00698                 ptr[4 * mb_x + 1] = buffer[mb_x][0] - ((buffer[mb_x][1] + buffer[mb_x][2]) >> 2);
00699                 ptr[4 * mb_x + 0] = buffer[mb_x][1] + ptr[4 * mb_x + 1];
00700                 ptr[4 * mb_x + 2] = buffer[mb_x][2] + ptr[4 * mb_x + 1];
00701             }
00702         } else {
00703             for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
00704                 ptr[4 * mb_x + 0] = buffer[mb_x][2];
00705                 ptr[4 * mb_x + 1] = buffer[mb_x][1];
00706                 ptr[4 * mb_x + 2] = buffer[mb_x][0];
00707             }
00708         }
00709     }
00710     return 0;
00711 }
00712 
00713 static int ljpeg_decode_yuv_scan(MJpegDecodeContext *s, int predictor,
00714                                  int point_transform)
00715 {
00716     int i, mb_x, mb_y;
00717     const int nb_components = 3;
00718 
00719     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
00720         for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
00721             if (s->restart_interval && !s->restart_count)
00722                 s->restart_count = s->restart_interval;
00723 
00724             if (mb_x == 0 || mb_y == 0 || s->interlaced) {
00725                 for (i = 0; i < nb_components; i++) {
00726                     uint8_t *ptr;
00727                     int n, h, v, x, y, c, j, linesize;
00728                     n        = s->nb_blocks[i];
00729                     c        = s->comp_index[i];
00730                     h        = s->h_scount[i];
00731                     v        = s->v_scount[i];
00732                     x        = 0;
00733                     y        = 0;
00734                     linesize = s->linesize[c];
00735 
00736                     for (j = 0; j < n; j++) {
00737                         int pred;
00738                         // FIXME optimize this crap
00739                         ptr = s->picture_ptr->data[c] +
00740                               (linesize * (v * mb_y + y)) +
00741                               (h * mb_x + x);
00742                         if (y == 0 && mb_y == 0) {
00743                             if (x == 0 && mb_x == 0)
00744                                 pred = 128 << point_transform;
00745                             else
00746                                 pred = ptr[-1];
00747                         } else {
00748                             if (x == 0 && mb_x == 0)
00749                                 pred = ptr[-linesize];
00750                             else
00751                                 PREDICT(pred, ptr[-linesize - 1],
00752                                         ptr[-linesize], ptr[-1], predictor);
00753                        }
00754 
00755                         if (s->interlaced && s->bottom_field)
00756                             ptr += linesize >> 1;
00757                         *ptr = pred + (mjpeg_decode_dc(s, s->dc_index[i]) << point_transform);
00758 
00759                         if (++x == h) {
00760                             x = 0;
00761                             y++;
00762                         }
00763                     }
00764                 }
00765             } else {
00766                 for (i = 0; i < nb_components; i++) {
00767                     uint8_t *ptr;
00768                     int n, h, v, x, y, c, j, linesize;
00769                     n        = s->nb_blocks[i];
00770                     c        = s->comp_index[i];
00771                     h        = s->h_scount[i];
00772                     v        = s->v_scount[i];
00773                     x        = 0;
00774                     y        = 0;
00775                     linesize = s->linesize[c];
00776 
00777                     for (j = 0; j < n; j++) {
00778                         int pred;
00779 
00780                         // FIXME optimize this crap
00781                         ptr = s->picture_ptr->data[c] +
00782                               (linesize * (v * mb_y + y)) +
00783                               (h * mb_x + x);
00784                         PREDICT(pred, ptr[-linesize - 1],
00785                                 ptr[-linesize], ptr[-1], predictor);
00786                         *ptr = pred + (mjpeg_decode_dc(s, s->dc_index[i]) << point_transform);
00787                         if (++x == h) {
00788                             x = 0;
00789                             y++;
00790                         }
00791                     }
00792                 }
00793             }
00794             if (s->restart_interval && !--s->restart_count) {
00795                 align_get_bits(&s->gb);
00796                 skip_bits(&s->gb, 16); /* skip RSTn */
00797             }
00798         }
00799     }
00800     return 0;
00801 }
00802 
00803 static av_always_inline void mjpeg_copy_block(uint8_t *dst, const uint8_t *src,
00804                                               int linesize, int lowres)
00805 {
00806     switch (lowres) {
00807     case 0: copy_block8(dst, src, linesize, linesize, 8);
00808         break;
00809     case 1: copy_block4(dst, src, linesize, linesize, 4);
00810         break;
00811     case 2: copy_block2(dst, src, linesize, linesize, 2);
00812         break;
00813     case 3: *dst = *src;
00814         break;
00815     }
00816 }
00817 
00818 static int mjpeg_decode_scan(MJpegDecodeContext *s, int nb_components, int Ah,
00819                              int Al, const uint8_t *mb_bitmask,
00820                              const AVFrame *reference)
00821 {
00822     int i, mb_x, mb_y;
00823     uint8_t *data[MAX_COMPONENTS];
00824     const uint8_t *reference_data[MAX_COMPONENTS];
00825     int linesize[MAX_COMPONENTS];
00826     GetBitContext mb_bitmask_gb;
00827 
00828     if (mb_bitmask)
00829         init_get_bits(&mb_bitmask_gb, mb_bitmask, s->mb_width * s->mb_height);
00830 
00831     if (s->flipped && s->avctx->flags & CODEC_FLAG_EMU_EDGE) {
00832         av_log(s->avctx, AV_LOG_ERROR,
00833                "Can not flip image with CODEC_FLAG_EMU_EDGE set!\n");
00834         s->flipped = 0;
00835     }
00836 
00837     for (i = 0; i < nb_components; i++) {
00838         int c   = s->comp_index[i];
00839         data[c] = s->picture_ptr->data[c];
00840         reference_data[c] = reference ? reference->data[c] : NULL;
00841         linesize[c] = s->linesize[c];
00842         s->coefs_finished[c] |= 1;
00843         if (s->flipped) {
00844             // picture should be flipped upside-down for this codec
00845             int offset = (linesize[c] * (s->v_scount[i] *
00846                          (8 * s->mb_height - ((s->height / s->v_max) & 7)) - 1));
00847             data[c]           += offset;
00848             reference_data[c] += offset;
00849             linesize[c]       *= -1;
00850         }
00851     }
00852 
00853     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
00854         for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
00855             const int copy_mb = mb_bitmask && !get_bits1(&mb_bitmask_gb);
00856 
00857             if (s->restart_interval && !s->restart_count)
00858                 s->restart_count = s->restart_interval;
00859 
00860             if (get_bits_left(&s->gb) < 0) {
00861                 av_log(s->avctx, AV_LOG_ERROR, "overread %d\n",
00862                        -get_bits_left(&s->gb));
00863                 return -1;
00864             }
00865             for (i = 0; i < nb_components; i++) {
00866                 uint8_t *ptr;
00867                 int n, h, v, x, y, c, j;
00868                 int block_offset;
00869                 n = s->nb_blocks[i];
00870                 c = s->comp_index[i];
00871                 h = s->h_scount[i];
00872                 v = s->v_scount[i];
00873                 x = 0;
00874                 y = 0;
00875                 for (j = 0; j < n; j++) {
00876                     block_offset = (((linesize[c] * (v * mb_y + y) * 8) +
00877                                      (h * mb_x + x) * 8) >> s->avctx->lowres);
00878 
00879                     if (s->interlaced && s->bottom_field)
00880                         block_offset += linesize[c] >> 1;
00881                     ptr = data[c] + block_offset;
00882                     if (!s->progressive) {
00883                         if (copy_mb)
00884                             mjpeg_copy_block(ptr, reference_data[c] + block_offset,
00885                                              linesize[c], s->avctx->lowres);
00886                         else {
00887                             s->dsp.clear_block(s->block);
00888                             if (decode_block(s, s->block, i,
00889                                              s->dc_index[i], s->ac_index[i],
00890                                              s->quant_matrixes[s->quant_index[c]]) < 0) {
00891                                 av_log(s->avctx, AV_LOG_ERROR,
00892                                        "error y=%d x=%d\n", mb_y, mb_x);
00893                                 return -1;
00894                             }
00895                             s->dsp.idct_put(ptr, linesize[c], s->block);
00896                         }
00897                     } else {
00898                         int block_idx  = s->block_stride[c] * (v * mb_y + y) +
00899                                          (h * mb_x + x);
00900                         DCTELEM *block = s->blocks[c][block_idx];
00901                         if (Ah)
00902                             block[0] += get_bits1(&s->gb) *
00903                                         s->quant_matrixes[s->quant_index[c]][0] << Al;
00904                         else if (decode_dc_progressive(s, block, i, s->dc_index[i],
00905                                                        s->quant_matrixes[s->quant_index[c]],
00906                                                        Al) < 0) {
00907                             av_log(s->avctx, AV_LOG_ERROR,
00908                                    "error y=%d x=%d\n", mb_y, mb_x);
00909                             return -1;
00910                         }
00911                     }
00912                     // av_log(s->avctx, AV_LOG_DEBUG, "mb: %d %d processed\n",
00913                     //        mb_y, mb_x);
00914                     // av_log(NULL, AV_LOG_DEBUG, "%d %d %d %d %d %d %d %d \n",
00915                     //        mb_x, mb_y, x, y, c, s->bottom_field,
00916                     //        (v * mb_y + y) * 8, (h * mb_x + x) * 8);
00917                     if (++x == h) {
00918                         x = 0;
00919                         y++;
00920                     }
00921                 }
00922             }
00923 
00924             if (s->restart_interval) {
00925                 s->restart_count--;
00926                 i = 8 + ((-get_bits_count(&s->gb)) & 7);
00927                 /* skip RSTn */
00928                 if (show_bits(&s->gb, i) == (1 << i) - 1) {
00929                     int pos = get_bits_count(&s->gb);
00930                     align_get_bits(&s->gb);
00931                     while (get_bits_left(&s->gb) >= 8 && show_bits(&s->gb, 8) == 0xFF)
00932                         skip_bits(&s->gb, 8);
00933                     if ((get_bits(&s->gb, 8) & 0xF8) == 0xD0) {
00934                         for (i = 0; i < nb_components; i++) /* reset dc */
00935                             s->last_dc[i] = 1024;
00936                     } else
00937                         skip_bits_long(&s->gb, pos - get_bits_count(&s->gb));
00938                 }
00939             }
00940         }
00941     }
00942     return 0;
00943 }
00944 
00945 static int mjpeg_decode_scan_progressive_ac(MJpegDecodeContext *s, int ss,
00946                                             int se, int Ah, int Al,
00947                                             const uint8_t *mb_bitmask,
00948                                             const AVFrame *reference)
00949 {
00950     int mb_x, mb_y;
00951     int EOBRUN = 0;
00952     int c = s->comp_index[0];
00953     uint8_t *data = s->picture_ptr->data[c];
00954     const uint8_t *reference_data = reference ? reference->data[c] : NULL;
00955     int linesize  = s->linesize[c];
00956     int last_scan = 0;
00957     int16_t *quant_matrix = s->quant_matrixes[s->quant_index[c]];
00958     GetBitContext mb_bitmask_gb;
00959 
00960     if (mb_bitmask)
00961         init_get_bits(&mb_bitmask_gb, mb_bitmask, s->mb_width * s->mb_height);
00962 
00963     if (!Al) {
00964         s->coefs_finished[c] |= (1LL << (se + 1)) - (1LL << ss);
00965         last_scan = !~s->coefs_finished[c];
00966     }
00967 
00968     if (s->interlaced && s->bottom_field) {
00969         int offset      = linesize >> 1;
00970         data           += offset;
00971         reference_data += offset;
00972     }
00973 
00974     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
00975         int block_offset = (mb_y * linesize * 8 >> s->avctx->lowres);
00976         uint8_t *ptr     = data + block_offset;
00977         int block_idx    = mb_y * s->block_stride[c];
00978         DCTELEM (*block)[64] = &s->blocks[c][block_idx];
00979         uint8_t *last_nnz    = &s->last_nnz[c][block_idx];
00980         for (mb_x = 0; mb_x < s->mb_width; mb_x++, block++, last_nnz++) {
00981             const int copy_mb = mb_bitmask && !get_bits1(&mb_bitmask_gb);
00982 
00983             if (!copy_mb) {
00984                 int ret;
00985                 if (Ah)
00986                     ret = decode_block_refinement(s, *block, last_nnz, s->ac_index[0],
00987                                                   quant_matrix, ss, se, Al, &EOBRUN);
00988                 else
00989                     ret = decode_block_progressive(s, *block, last_nnz, s->ac_index[0],
00990                                                    quant_matrix, ss, se, Al, &EOBRUN);
00991                 if (ret < 0) {
00992                     av_log(s->avctx, AV_LOG_ERROR,
00993                            "error y=%d x=%d\n", mb_y, mb_x);
00994                     return -1;
00995                 }
00996             }
00997 
00998             if (last_scan) {
00999                 if (copy_mb) {
01000                     mjpeg_copy_block(ptr, reference_data + block_offset,
01001                                      linesize, s->avctx->lowres);
01002                 } else {
01003                     s->dsp.idct_put(ptr, linesize, *block);
01004                     ptr += 8 >> s->avctx->lowres;
01005                 }
01006             }
01007         }
01008     }
01009     return 0;
01010 }
01011 
01012 int ff_mjpeg_decode_sos(MJpegDecodeContext *s, const uint8_t *mb_bitmask,
01013                         const AVFrame *reference)
01014 {
01015     int len, nb_components, i, h, v, predictor, point_transform;
01016     int index, id;
01017     const int block_size = s->lossless ? 1 : 8;
01018     int ilv, prev_shift;
01019 
01020     /* XXX: verify len field validity */
01021     len = get_bits(&s->gb, 16);
01022     nb_components = get_bits(&s->gb, 8);
01023     if (nb_components == 0 || nb_components > MAX_COMPONENTS) {
01024         av_log(s->avctx, AV_LOG_ERROR,
01025                "decode_sos: nb_components (%d) unsupported\n", nb_components);
01026         return -1;
01027     }
01028     if (len != 6 + 2 * nb_components) {
01029         av_log(s->avctx, AV_LOG_ERROR, "decode_sos: invalid len (%d)\n", len);
01030         return -1;
01031     }
01032     for (i = 0; i < nb_components; i++) {
01033         id = get_bits(&s->gb, 8) - 1;
01034         av_log(s->avctx, AV_LOG_DEBUG, "component: %d\n", id);
01035         /* find component index */
01036         for (index = 0; index < s->nb_components; index++)
01037             if (id == s->component_id[index])
01038                 break;
01039         if (index == s->nb_components) {
01040             av_log(s->avctx, AV_LOG_ERROR,
01041                    "decode_sos: index(%d) out of components\n", index);
01042             return -1;
01043         }
01044         /* Metasoft MJPEG codec has Cb and Cr swapped */
01045         if (s->avctx->codec_tag == MKTAG('M', 'T', 'S', 'J')
01046             && nb_components == 3 && s->nb_components == 3 && i)
01047             index = 3 - i;
01048 
01049         s->comp_index[i] = index;
01050 
01051         s->nb_blocks[i] = s->h_count[index] * s->v_count[index];
01052         s->h_scount[i]  = s->h_count[index];
01053         s->v_scount[i]  = s->v_count[index];
01054 
01055         s->dc_index[i] = get_bits(&s->gb, 4);
01056         s->ac_index[i] = get_bits(&s->gb, 4);
01057 
01058         if (s->dc_index[i] <  0 || s->ac_index[i] < 0 ||
01059             s->dc_index[i] >= 4 || s->ac_index[i] >= 4)
01060             goto out_of_range;
01061         if (!s->vlcs[0][s->dc_index[i]].table ||
01062             !s->vlcs[1][s->ac_index[i]].table)
01063             goto out_of_range;
01064     }
01065 
01066     predictor = get_bits(&s->gb, 8);       /* JPEG Ss / lossless JPEG predictor /JPEG-LS NEAR */
01067     ilv = get_bits(&s->gb, 8);             /* JPEG Se / JPEG-LS ILV */
01068     prev_shift      = get_bits(&s->gb, 4); /* Ah */
01069     point_transform = get_bits(&s->gb, 4); /* Al */
01070 
01071     for (i = 0; i < nb_components; i++)
01072         s->last_dc[i] = 1024;
01073 
01074     if (nb_components > 1) {
01075         /* interleaved stream */
01076         s->mb_width  = (s->width  + s->h_max * block_size - 1) / (s->h_max * block_size);
01077         s->mb_height = (s->height + s->v_max * block_size - 1) / (s->v_max * block_size);
01078     } else if (!s->ls) { /* skip this for JPEG-LS */
01079         h = s->h_max / s->h_scount[0];
01080         v = s->v_max / s->v_scount[0];
01081         s->mb_width     = (s->width  + h * block_size - 1) / (h * block_size);
01082         s->mb_height    = (s->height + v * block_size - 1) / (v * block_size);
01083         s->nb_blocks[0] = 1;
01084         s->h_scount[0]  = 1;
01085         s->v_scount[0]  = 1;
01086     }
01087 
01088     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01089         av_log(s->avctx, AV_LOG_DEBUG, "%s %s p:%d >>:%d ilv:%d bits:%d %s\n",
01090                s->lossless ? "lossless" : "sequential DCT", s->rgb ? "RGB" : "",
01091                predictor, point_transform, ilv, s->bits,
01092                s->pegasus_rct ? "PRCT" : (s->rct ? "RCT" : ""));
01093 
01094 
01095     /* mjpeg-b can have padding bytes between sos and image data, skip them */
01096     for (i = s->mjpb_skiptosod; i > 0; i--)
01097         skip_bits(&s->gb, 8);
01098 
01099     if (s->lossless) {
01100         if (CONFIG_JPEGLS_DECODER && s->ls) {
01101 //            for () {
01102 //            reset_ls_coding_parameters(s, 0);
01103 
01104             if (ff_jpegls_decode_picture(s, predictor, point_transform, ilv) < 0)
01105                 return -1;
01106         } else {
01107             if (s->rgb) {
01108                 if (ljpeg_decode_rgb_scan(s, predictor, point_transform) < 0)
01109                     return -1;
01110             } else {
01111                 if (ljpeg_decode_yuv_scan(s, predictor, point_transform) < 0)
01112                     return -1;
01113             }
01114         }
01115     } else {
01116         if (s->progressive && predictor) {
01117             if (mjpeg_decode_scan_progressive_ac(s, predictor, ilv, prev_shift,
01118                                                  point_transform,
01119                                                  mb_bitmask, reference) < 0)
01120                 return -1;
01121         } else {
01122             if (mjpeg_decode_scan(s, nb_components, prev_shift, point_transform,
01123                                   mb_bitmask, reference) < 0)
01124                 return -1;
01125         }
01126     }
01127     emms_c();
01128     return 0;
01129  out_of_range:
01130     av_log(s->avctx, AV_LOG_ERROR, "decode_sos: ac/dc index out of range\n");
01131     return -1;
01132 }
01133 
01134 static int mjpeg_decode_dri(MJpegDecodeContext *s)
01135 {
01136     if (get_bits(&s->gb, 16) != 4)
01137         return -1;
01138     s->restart_interval = get_bits(&s->gb, 16);
01139     s->restart_count    = 0;
01140     av_log(s->avctx, AV_LOG_DEBUG, "restart interval: %d\n",
01141            s->restart_interval);
01142 
01143     return 0;
01144 }
01145 
01146 static int mjpeg_decode_app(MJpegDecodeContext *s)
01147 {
01148     int len, id, i;
01149 
01150     len = get_bits(&s->gb, 16);
01151     if (len < 5)
01152         return -1;
01153     if (8 * len > get_bits_left(&s->gb))
01154         return -1;
01155 
01156     id   = get_bits_long(&s->gb, 32);
01157     id   = av_be2ne32(id);
01158     len -= 6;
01159 
01160     if (s->avctx->debug & FF_DEBUG_STARTCODE)
01161         av_log(s->avctx, AV_LOG_DEBUG, "APPx %8X\n", id);
01162 
01163     /* Buggy AVID, it puts EOI only at every 10th frame. */
01164     /* Also, this fourcc is used by non-avid files too, it holds some
01165        information, but it's always present in AVID-created files. */
01166     if (id == AV_RL32("AVI1")) {
01167         /* structure:
01168             4bytes      AVI1
01169             1bytes      polarity
01170             1bytes      always zero
01171             4bytes      field_size
01172             4bytes      field_size_less_padding
01173         */
01174         s->buggy_avid = 1;
01175 //      if (s->first_picture)
01176 //          printf("mjpeg: workarounding buggy AVID\n");
01177         i = get_bits(&s->gb, 8);
01178         if (i == 2)
01179             s->bottom_field = 1;
01180         else if (i == 1)
01181             s->bottom_field = 0;
01182 #if 0
01183         skip_bits(&s->gb, 8);
01184         skip_bits(&s->gb, 32);
01185         skip_bits(&s->gb, 32);
01186         len -= 10;
01187 #endif
01188 //        if (s->interlace_polarity)
01189 //            printf("mjpeg: interlace polarity: %d\n", s->interlace_polarity);
01190         goto out;
01191     }
01192 
01193 //    len -= 2;
01194 
01195     if (id == AV_RL32("JFIF")) {
01196         int t_w, t_h, v1, v2;
01197         skip_bits(&s->gb, 8); /* the trailing zero-byte */
01198         v1 = get_bits(&s->gb, 8);
01199         v2 = get_bits(&s->gb, 8);
01200         skip_bits(&s->gb, 8);
01201 
01202         s->avctx->sample_aspect_ratio.num = get_bits(&s->gb, 16);
01203         s->avctx->sample_aspect_ratio.den = get_bits(&s->gb, 16);
01204 
01205         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01206             av_log(s->avctx, AV_LOG_INFO,
01207                    "mjpeg: JFIF header found (version: %x.%x) SAR=%d/%d\n",
01208                    v1, v2,
01209                    s->avctx->sample_aspect_ratio.num,
01210                    s->avctx->sample_aspect_ratio.den);
01211 
01212         t_w = get_bits(&s->gb, 8);
01213         t_h = get_bits(&s->gb, 8);
01214         if (t_w && t_h) {
01215             /* skip thumbnail */
01216             if (len -10 - (t_w * t_h * 3) > 0)
01217                 len -= t_w * t_h * 3;
01218         }
01219         len -= 10;
01220         goto out;
01221     }
01222 
01223     if (id == AV_RL32("Adob") && (get_bits(&s->gb, 8) == 'e')) {
01224         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01225             av_log(s->avctx, AV_LOG_INFO, "mjpeg: Adobe header found\n");
01226         skip_bits(&s->gb, 16); /* version */
01227         skip_bits(&s->gb, 16); /* flags0 */
01228         skip_bits(&s->gb, 16); /* flags1 */
01229         skip_bits(&s->gb,  8); /* transform */
01230         len -= 7;
01231         goto out;
01232     }
01233 
01234     if (id == AV_RL32("LJIF")) {
01235         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01236             av_log(s->avctx, AV_LOG_INFO,
01237                    "Pegasus lossless jpeg header found\n");
01238         skip_bits(&s->gb, 16); /* version ? */
01239         skip_bits(&s->gb, 16); /* unknwon always 0? */
01240         skip_bits(&s->gb, 16); /* unknwon always 0? */
01241         skip_bits(&s->gb, 16); /* unknwon always 0? */
01242         switch (get_bits(&s->gb, 8)) {
01243         case 1:
01244             s->rgb         = 1;
01245             s->pegasus_rct = 0;
01246             break;
01247         case 2:
01248             s->rgb         = 1;
01249             s->pegasus_rct = 1;
01250             break;
01251         default:
01252             av_log(s->avctx, AV_LOG_ERROR, "unknown colorspace\n");
01253         }
01254         len -= 9;
01255         goto out;
01256     }
01257 
01258     /* Apple MJPEG-A */
01259     if ((s->start_code == APP1) && (len > (0x28 - 8))) {
01260         id   = get_bits_long(&s->gb, 32);
01261         id   = av_be2ne32(id);
01262         len -= 4;
01263         /* Apple MJPEG-A */
01264         if (id == AV_RL32("mjpg")) {
01265 #if 0
01266             skip_bits(&s->gb, 32); /* field size */
01267             skip_bits(&s->gb, 32); /* pad field size */
01268             skip_bits(&s->gb, 32); /* next off */
01269             skip_bits(&s->gb, 32); /* quant off */
01270             skip_bits(&s->gb, 32); /* huff off */
01271             skip_bits(&s->gb, 32); /* image off */
01272             skip_bits(&s->gb, 32); /* scan off */
01273             skip_bits(&s->gb, 32); /* data off */
01274 #endif
01275             if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01276                 av_log(s->avctx, AV_LOG_INFO, "mjpeg: Apple MJPEG-A header found\n");
01277         }
01278     }
01279 
01280 out:
01281     /* slow but needed for extreme adobe jpegs */
01282     if (len < 0)
01283         av_log(s->avctx, AV_LOG_ERROR,
01284                "mjpeg: error, decode_app parser read over the end\n");
01285     while (--len > 0)
01286         skip_bits(&s->gb, 8);
01287 
01288     return 0;
01289 }
01290 
01291 static int mjpeg_decode_com(MJpegDecodeContext *s)
01292 {
01293     int len = get_bits(&s->gb, 16);
01294     if (len >= 2 && 8 * len - 16 <= get_bits_left(&s->gb)) {
01295         char *cbuf = av_malloc(len - 1);
01296         if (cbuf) {
01297             int i;
01298             for (i = 0; i < len - 2; i++)
01299                 cbuf[i] = get_bits(&s->gb, 8);
01300             if (i > 0 && cbuf[i - 1] == '\n')
01301                 cbuf[i - 1] = 0;
01302             else
01303                 cbuf[i] = 0;
01304 
01305             if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01306                 av_log(s->avctx, AV_LOG_INFO, "mjpeg comment: '%s'\n", cbuf);
01307 
01308             /* buggy avid, it puts EOI only at every 10th frame */
01309             if (!strcmp(cbuf, "AVID")) {
01310                 s->buggy_avid = 1;
01311                 // if (s->first_picture)
01312                 // printf("mjpeg: workarounding buggy AVID\n");
01313             } else if (!strcmp(cbuf, "CS=ITU601"))
01314                 s->cs_itu601 = 1;
01315             else if ((len > 20 && !strncmp(cbuf, "Intel(R) JPEG Library", 21)) ||
01316                      (len > 19 && !strncmp(cbuf, "Metasoft MJPEG Codec", 20)))
01317                 s->flipped = 1;
01318 
01319             av_free(cbuf);
01320         }
01321     }
01322 
01323     return 0;
01324 }
01325 
01326 /* return the 8 bit start code value and update the search
01327    state. Return -1 if no start code found */
01328 static int find_marker(const uint8_t **pbuf_ptr, const uint8_t *buf_end)
01329 {
01330     const uint8_t *buf_ptr;
01331     unsigned int v, v2;
01332     int val;
01333 #ifdef DEBUG
01334     int skipped = 0;
01335 #endif
01336 
01337     buf_ptr = *pbuf_ptr;
01338     while (buf_ptr < buf_end) {
01339         v  = *buf_ptr++;
01340         v2 = *buf_ptr;
01341         if ((v == 0xff) && (v2 >= 0xc0) && (v2 <= 0xfe) && buf_ptr < buf_end) {
01342             val = *buf_ptr++;
01343             goto found;
01344         }
01345 #ifdef DEBUG
01346         skipped++;
01347 #endif
01348     }
01349     val = -1;
01350 found:
01351     av_dlog(NULL, "find_marker skipped %d bytes\n", skipped);
01352     *pbuf_ptr = buf_ptr;
01353     return val;
01354 }
01355 
01356 int ff_mjpeg_find_marker(MJpegDecodeContext *s,
01357                          const uint8_t **buf_ptr, const uint8_t *buf_end,
01358                          const uint8_t **unescaped_buf_ptr,
01359                          int *unescaped_buf_size)
01360 {
01361     int start_code;
01362     start_code = find_marker(buf_ptr, buf_end);
01363 
01364     if ((buf_end - *buf_ptr) > s->buffer_size) {
01365         av_free(s->buffer);
01366         s->buffer_size = buf_end - *buf_ptr;
01367         s->buffer      = av_malloc(s->buffer_size + FF_INPUT_BUFFER_PADDING_SIZE);
01368         av_log(s->avctx, AV_LOG_DEBUG,
01369                "buffer too small, expanding to %d bytes\n", s->buffer_size);
01370     }
01371 
01372     /* unescape buffer of SOS, use special treatment for JPEG-LS */
01373     if (start_code == SOS && !s->ls) {
01374         const uint8_t *src = *buf_ptr;
01375         uint8_t *dst = s->buffer;
01376 
01377         while (src < buf_end) {
01378             uint8_t x = *(src++);
01379 
01380             *(dst++) = x;
01381             if (s->avctx->codec_id != CODEC_ID_THP) {
01382                 if (x == 0xff) {
01383                     while (src < buf_end && x == 0xff)
01384                         x = *(src++);
01385 
01386                     if (x >= 0xd0 && x <= 0xd7)
01387                         *(dst++) = x;
01388                     else if (x)
01389                         break;
01390                 }
01391             }
01392         }
01393         *unescaped_buf_ptr  = s->buffer;
01394         *unescaped_buf_size = dst - s->buffer;
01395 
01396         av_log(s->avctx, AV_LOG_DEBUG, "escaping removed %td bytes\n",
01397                (buf_end - *buf_ptr) - (dst - s->buffer));
01398     } else if (start_code == SOS && s->ls) {
01399         const uint8_t *src = *buf_ptr;
01400         uint8_t *dst  = s->buffer;
01401         int bit_count = 0;
01402         int t = 0, b = 0;
01403         PutBitContext pb;
01404 
01405         s->cur_scan++;
01406 
01407         /* find marker */
01408         while (src + t < buf_end) {
01409             uint8_t x = src[t++];
01410             if (x == 0xff) {
01411                 while ((src + t < buf_end) && x == 0xff)
01412                     x = src[t++];
01413                 if (x & 0x80) {
01414                     t -= 2;
01415                     break;
01416                 }
01417             }
01418         }
01419         bit_count = t * 8;
01420         init_put_bits(&pb, dst, t);
01421 
01422         /* unescape bitstream */
01423         while (b < t) {
01424             uint8_t x = src[b++];
01425             put_bits(&pb, 8, x);
01426             if (x == 0xFF) {
01427                 x = src[b++];
01428                 put_bits(&pb, 7, x);
01429                 bit_count--;
01430             }
01431         }
01432         flush_put_bits(&pb);
01433 
01434         *unescaped_buf_ptr  = dst;
01435         *unescaped_buf_size = (bit_count + 7) >> 3;
01436     } else {
01437         *unescaped_buf_ptr  = *buf_ptr;
01438         *unescaped_buf_size = buf_end - *buf_ptr;
01439     }
01440 
01441     return start_code;
01442 }
01443 
01444 int ff_mjpeg_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
01445                           AVPacket *avpkt)
01446 {
01447     const uint8_t *buf = avpkt->data;
01448     int buf_size       = avpkt->size;
01449     MJpegDecodeContext *s = avctx->priv_data;
01450     const uint8_t *buf_end, *buf_ptr;
01451     const uint8_t *unescaped_buf_ptr;
01452     int unescaped_buf_size;
01453     int start_code;
01454     AVFrame *picture = data;
01455 
01456     s->got_picture = 0; // picture from previous image can not be reused
01457     buf_ptr = buf;
01458     buf_end = buf + buf_size;
01459     while (buf_ptr < buf_end) {
01460         /* find start next marker */
01461         start_code = ff_mjpeg_find_marker(s, &buf_ptr, buf_end,
01462                                           &unescaped_buf_ptr,
01463                                           &unescaped_buf_size);
01464         /* EOF */
01465         if (start_code < 0) {
01466             goto the_end;
01467         } else if (unescaped_buf_size > (1U<<29)) {
01468             av_log(avctx, AV_LOG_ERROR, "MJPEG packet 0x%x too big (0x%x/0x%x), corrupt data?\n",
01469                    start_code, unescaped_buf_ptr, buf_size);
01470             return AVERROR_INVALIDDATA;
01471         } else {
01472             av_log(avctx, AV_LOG_DEBUG, "marker=%x avail_size_in_buf=%td\n",
01473                    start_code, buf_end - buf_ptr);
01474 
01475             init_get_bits(&s->gb, unescaped_buf_ptr, unescaped_buf_size * 8);
01476 
01477             s->start_code = start_code;
01478             if (s->avctx->debug & FF_DEBUG_STARTCODE)
01479                 av_log(avctx, AV_LOG_DEBUG, "startcode: %X\n", start_code);
01480 
01481             /* process markers */
01482             if (start_code >= 0xd0 && start_code <= 0xd7)
01483                 av_log(avctx, AV_LOG_DEBUG,
01484                        "restart marker: %d\n", start_code & 0x0f);
01485                 /* APP fields */
01486             else if (start_code >= APP0 && start_code <= APP15)
01487                 mjpeg_decode_app(s);
01488                 /* Comment */
01489             else if (start_code == COM)
01490                 mjpeg_decode_com(s);
01491 
01492             switch (start_code) {
01493             case SOI:
01494                 s->restart_interval = 0;
01495                 s->restart_count    = 0;
01496                 /* nothing to do on SOI */
01497                 break;
01498             case DQT:
01499                 ff_mjpeg_decode_dqt(s);
01500                 break;
01501             case DHT:
01502                 if (ff_mjpeg_decode_dht(s) < 0) {
01503                     av_log(avctx, AV_LOG_ERROR, "huffman table decode error\n");
01504                     return -1;
01505                 }
01506                 break;
01507             case SOF0:
01508             case SOF1:
01509                 s->lossless    = 0;
01510                 s->ls          = 0;
01511                 s->progressive = 0;
01512                 if (ff_mjpeg_decode_sof(s) < 0)
01513                     return -1;
01514                 break;
01515             case SOF2:
01516                 s->lossless    = 0;
01517                 s->ls          = 0;
01518                 s->progressive = 1;
01519                 if (ff_mjpeg_decode_sof(s) < 0)
01520                     return -1;
01521                 break;
01522             case SOF3:
01523                 s->lossless    = 1;
01524                 s->ls          = 0;
01525                 s->progressive = 0;
01526                 if (ff_mjpeg_decode_sof(s) < 0)
01527                     return -1;
01528                 break;
01529             case SOF48:
01530                 s->lossless    = 1;
01531                 s->ls          = 1;
01532                 s->progressive = 0;
01533                 if (ff_mjpeg_decode_sof(s) < 0)
01534                     return -1;
01535                 break;
01536             case LSE:
01537                 if (!CONFIG_JPEGLS_DECODER || ff_jpegls_decode_lse(s) < 0)
01538                     return -1;
01539                 break;
01540             case EOI:
01541                 s->cur_scan = 0;
01542                 if ((s->buggy_avid && !s->interlaced) || s->restart_interval)
01543                     break;
01544 eoi_parser:
01545                 if (!s->got_picture) {
01546                     av_log(avctx, AV_LOG_WARNING,
01547                            "Found EOI before any SOF, ignoring\n");
01548                     break;
01549                     }
01550                 if (s->interlaced) {
01551                     s->bottom_field ^= 1;
01552                     /* if not bottom field, do not output image yet */
01553                     if (s->bottom_field == !s->interlace_polarity)
01554                         goto not_the_end;
01555                     }
01556                     *picture   = *s->picture_ptr;
01557                     *data_size = sizeof(AVFrame);
01558 
01559                     if (!s->lossless) {
01560                         picture->quality      = FFMAX3(s->qscale[0],
01561                                                        s->qscale[1],
01562                                                        s->qscale[2]);
01563                         picture->qstride      = 0;
01564                         picture->qscale_table = s->qscale_table;
01565                         memset(picture->qscale_table, picture->quality,
01566                                (s->width + 15) / 16);
01567                         if (avctx->debug & FF_DEBUG_QP)
01568                             av_log(avctx, AV_LOG_DEBUG,
01569                                    "QP: %d\n", picture->quality);
01570                         picture->quality *= FF_QP2LAMBDA;
01571                     }
01572 
01573                 goto the_end;
01574             case SOS:
01575                 if (!s->got_picture) {
01576                     av_log(avctx, AV_LOG_WARNING,
01577                            "Can not process SOS before SOF, skipping\n");
01578                     break;
01579                     }
01580                 if (ff_mjpeg_decode_sos(s, NULL, NULL) < 0 &&
01581                     (avctx->err_recognition & AV_EF_EXPLODE))
01582                     return AVERROR_INVALIDDATA;
01583                 /* buggy avid puts EOI every 10-20th frame */
01584                 /* if restart period is over process EOI */
01585                 if ((s->buggy_avid && !s->interlaced) || s->restart_interval)
01586                     goto eoi_parser;
01587                 break;
01588             case DRI:
01589                 mjpeg_decode_dri(s);
01590                 break;
01591             case SOF5:
01592             case SOF6:
01593             case SOF7:
01594             case SOF9:
01595             case SOF10:
01596             case SOF11:
01597             case SOF13:
01598             case SOF14:
01599             case SOF15:
01600             case JPG:
01601                 av_log(avctx, AV_LOG_ERROR,
01602                        "mjpeg: unsupported coding type (%x)\n", start_code);
01603                 break;
01604 //              default:
01605 //              printf("mjpeg: unsupported marker (%x)\n", start_code);
01606 //              break;
01607             }
01608 
01609 not_the_end:
01610             /* eof process start code */
01611             buf_ptr += (get_bits_count(&s->gb) + 7) / 8;
01612             av_log(avctx, AV_LOG_DEBUG,
01613                    "marker parser used %d bytes (%d bits)\n",
01614                    (get_bits_count(&s->gb) + 7) / 8, get_bits_count(&s->gb));
01615         }
01616     }
01617     if (s->got_picture) {
01618         av_log(avctx, AV_LOG_WARNING, "EOI missing, emulating\n");
01619         goto eoi_parser;
01620     }
01621     av_log(avctx, AV_LOG_FATAL, "No JPEG data found in image\n");
01622     return -1;
01623 the_end:
01624     av_log(avctx, AV_LOG_DEBUG, "mjpeg decode frame unused %td bytes\n",
01625            buf_end - buf_ptr);
01626 //  return buf_end - buf_ptr;
01627     return buf_ptr - buf;
01628 }
01629 
01630 av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
01631 {
01632     MJpegDecodeContext *s = avctx->priv_data;
01633     int i, j;
01634 
01635     if (s->picture_ptr && s->picture_ptr->data[0])
01636         avctx->release_buffer(avctx, s->picture_ptr);
01637 
01638     av_free(s->buffer);
01639     av_free(s->qscale_table);
01640     av_freep(&s->ljpeg_buffer);
01641     s->ljpeg_buffer_size = 0;
01642 
01643     for (i = 0; i < 3; i++) {
01644         for (j = 0; j < 4; j++)
01645             ff_free_vlc(&s->vlcs[i][j]);
01646     }
01647     for (i = 0; i < MAX_COMPONENTS; i++) {
01648         av_freep(&s->blocks[i]);
01649         av_freep(&s->last_nnz[i]);
01650     }
01651     return 0;
01652 }
01653 
01654 #define OFFSET(x) offsetof(MJpegDecodeContext, x)
01655 #define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
01656 static const AVOption options[] = {
01657     { "extern_huff", "Use external huffman table.",
01658       OFFSET(extern_huff), AV_OPT_TYPE_INT, { 0 }, 0, 1, VD },
01659     { NULL },
01660 };
01661 
01662 static const AVClass mjpegdec_class = {
01663     .class_name = "MJPEG decoder",
01664     .item_name  = av_default_item_name,
01665     .option     = options,
01666     .version    = LIBAVUTIL_VERSION_INT,
01667 };
01668 
01669 AVCodec ff_mjpeg_decoder = {
01670     .name           = "mjpeg",
01671     .type           = AVMEDIA_TYPE_VIDEO,
01672     .id             = CODEC_ID_MJPEG,
01673     .priv_data_size = sizeof(MJpegDecodeContext),
01674     .init           = ff_mjpeg_decode_init,
01675     .close          = ff_mjpeg_decode_end,
01676     .decode         = ff_mjpeg_decode_frame,
01677     .capabilities   = CODEC_CAP_DR1,
01678     .max_lowres     = 3,
01679     .long_name      = NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),
01680     .priv_class     = &mjpegdec_class,
01681 };
01682 
01683 AVCodec ff_thp_decoder = {
01684     .name           = "thp",
01685     .type           = AVMEDIA_TYPE_VIDEO,
01686     .id             = CODEC_ID_THP,
01687     .priv_data_size = sizeof(MJpegDecodeContext),
01688     .init           = ff_mjpeg_decode_init,
01689     .close          = ff_mjpeg_decode_end,
01690     .decode         = ff_mjpeg_decode_frame,
01691     .capabilities   = CODEC_CAP_DR1,
01692     .max_lowres     = 3,
01693     .long_name      = NULL_IF_CONFIG_SMALL("Nintendo Gamecube THP video"),
01694 };