Libav

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 FFmpeg.
00012  *
00013  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 "avcodec.h"
00037 #include "dsputil.h"
00038 #include "mjpeg.h"
00039 #include "mjpegdec.h"
00040 #include "jpeglsdec.h"
00041 
00042 
00043 static int build_vlc(VLC *vlc, const uint8_t *bits_table, const uint8_t *val_table,
00044                       int nb_codes, int use_static, int is_ac)
00045 {
00046     uint8_t huff_size[256+16];
00047     uint16_t huff_code[256+16];
00048 
00049     assert(nb_codes <= 256);
00050 
00051     memset(huff_size, 0, sizeof(huff_size));
00052     ff_mjpeg_build_huffman_codes(huff_size, huff_code, bits_table, val_table);
00053 
00054     if(is_ac){
00055         memmove(huff_size+16, huff_size, sizeof(uint8_t)*nb_codes);
00056         memmove(huff_code+16, huff_code, sizeof(uint16_t)*nb_codes);
00057         memset(huff_size, 0, sizeof(uint8_t)*16);
00058         memset(huff_code, 0, sizeof(uint16_t)*16);
00059         nb_codes += 16;
00060     }
00061 
00062     return init_vlc(vlc, 9, nb_codes, huff_size, 1, 1, huff_code, 2, 2, use_static);
00063 }
00064 
00065 static void build_basic_mjpeg_vlc(MJpegDecodeContext * s) {
00066     build_vlc(&s->vlcs[0][0], ff_mjpeg_bits_dc_luminance,
00067               ff_mjpeg_val_dc, 12, 0, 0);
00068     build_vlc(&s->vlcs[0][1], ff_mjpeg_bits_dc_chrominance,
00069               ff_mjpeg_val_dc, 12, 0, 0);
00070     build_vlc(&s->vlcs[1][0], ff_mjpeg_bits_ac_luminance,
00071               ff_mjpeg_val_ac_luminance, 251, 0, 1);
00072     build_vlc(&s->vlcs[1][1], ff_mjpeg_bits_ac_chrominance,
00073               ff_mjpeg_val_ac_chrominance, 251, 0, 1);
00074 }
00075 
00076 av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)
00077 {
00078     MJpegDecodeContext *s = avctx->priv_data;
00079 
00080     s->avctx = avctx;
00081     dsputil_init(&s->dsp, avctx);
00082     ff_init_scantable(s->dsp.idct_permutation, &s->scantable, ff_zigzag_direct);
00083     s->buffer_size = 0;
00084     s->buffer = NULL;
00085     s->start_code = -1;
00086     s->first_picture = 1;
00087     s->org_height = avctx->coded_height;
00088     avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
00089 
00090     build_basic_mjpeg_vlc(s);
00091 
00092     if (avctx->flags & CODEC_FLAG_EXTERN_HUFF)
00093     {
00094         av_log(avctx, AV_LOG_INFO, "mjpeg: using external huffman table\n");
00095         init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size*8);
00096         if (ff_mjpeg_decode_dht(s)) {
00097             av_log(avctx, AV_LOG_ERROR, "mjpeg: error using external huffman table, switching back to internal\n");
00098             build_basic_mjpeg_vlc(s);
00099         }
00100     }
00101     if (avctx->extradata_size > 9 &&
00102         AV_RL32(avctx->extradata + 4) == MKTAG('f','i','e','l')) {
00103         if (avctx->extradata[9] == 6) { /* quicktime icefloe 019 */
00104             s->interlace_polarity = 1; /* bottom field first */
00105             av_log(avctx, AV_LOG_DEBUG, "mjpeg bottom field first\n");
00106         }
00107     }
00108     if (avctx->codec->id == CODEC_ID_AMV)
00109         s->flipped = 1;
00110 
00111     return 0;
00112 }
00113 
00114 
00115 /* quantize tables */
00116 int ff_mjpeg_decode_dqt(MJpegDecodeContext *s)
00117 {
00118     int len, index, i, j;
00119 
00120     len = get_bits(&s->gb, 16) - 2;
00121 
00122     while (len >= 65) {
00123         /* only 8 bit precision handled */
00124         if (get_bits(&s->gb, 4) != 0)
00125         {
00126             av_log(s->avctx, AV_LOG_ERROR, "dqt: 16bit precision\n");
00127             return -1;
00128         }
00129         index = get_bits(&s->gb, 4);
00130         if (index >= 4)
00131             return -1;
00132         av_log(s->avctx, AV_LOG_DEBUG, "index=%d\n", index);
00133         /* read quant table */
00134         for(i=0;i<64;i++) {
00135             j = s->scantable.permutated[i];
00136             s->quant_matrixes[index][j] = get_bits(&s->gb, 8);
00137         }
00138 
00139         //XXX FIXME finetune, and perhaps add dc too
00140         s->qscale[index]= FFMAX(
00141             s->quant_matrixes[index][s->scantable.permutated[1]],
00142             s->quant_matrixes[index][s->scantable.permutated[8]]) >> 1;
00143         av_log(s->avctx, AV_LOG_DEBUG, "qscale[%d]: %d\n", index, s->qscale[index]);
00144         len -= 65;
00145     }
00146 
00147     return 0;
00148 }
00149 
00150 /* decode huffman tables and build VLC decoders */
00151 int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
00152 {
00153     int len, index, i, class, n, v, code_max;
00154     uint8_t bits_table[17];
00155     uint8_t val_table[256];
00156 
00157     len = get_bits(&s->gb, 16) - 2;
00158 
00159     while (len > 0) {
00160         if (len < 17)
00161             return -1;
00162         class = get_bits(&s->gb, 4);
00163         if (class >= 2)
00164             return -1;
00165         index = get_bits(&s->gb, 4);
00166         if (index >= 4)
00167             return -1;
00168         n = 0;
00169         for(i=1;i<=16;i++) {
00170             bits_table[i] = get_bits(&s->gb, 8);
00171             n += bits_table[i];
00172         }
00173         len -= 17;
00174         if (len < n || n > 256)
00175             return -1;
00176 
00177         code_max = 0;
00178         for(i=0;i<n;i++) {
00179             v = get_bits(&s->gb, 8);
00180             if (v > code_max)
00181                 code_max = v;
00182             val_table[i] = v;
00183         }
00184         len -= n;
00185 
00186         /* build VLC and flush previous vlc if present */
00187         free_vlc(&s->vlcs[class][index]);
00188         av_log(s->avctx, AV_LOG_DEBUG, "class=%d index=%d nb_codes=%d\n",
00189                class, index, code_max + 1);
00190         if(build_vlc(&s->vlcs[class][index], bits_table, val_table, code_max + 1, 0, class > 0) < 0){
00191             return -1;
00192         }
00193     }
00194     return 0;
00195 }
00196 
00197 int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
00198 {
00199     int len, nb_components, i, width, height, pix_fmt_id;
00200 
00201     /* XXX: verify len field validity */
00202     len = get_bits(&s->gb, 16);
00203     s->bits= get_bits(&s->gb, 8);
00204 
00205     if(s->pegasus_rct) s->bits=9;
00206     if(s->bits==9 && !s->pegasus_rct) s->rct=1;    //FIXME ugly
00207 
00208     if (s->bits != 8 && !s->lossless){
00209         av_log(s->avctx, AV_LOG_ERROR, "only 8 bits/component accepted\n");
00210         return -1;
00211     }
00212 
00213     height = get_bits(&s->gb, 16);
00214     width = get_bits(&s->gb, 16);
00215 
00216     //HACK for odd_height.mov
00217     if(s->interlaced && s->width == width && s->height == height + 1)
00218         height= s->height;
00219 
00220     av_log(s->avctx, AV_LOG_DEBUG, "sof0: picture: %dx%d\n", width, height);
00221     if(avcodec_check_dimensions(s->avctx, width, height))
00222         return -1;
00223 
00224     nb_components = get_bits(&s->gb, 8);
00225     if (nb_components <= 0 ||
00226         nb_components > MAX_COMPONENTS)
00227         return -1;
00228     if (s->ls && !(s->bits <= 8 || nb_components == 1)){
00229         av_log(s->avctx, AV_LOG_ERROR, "only <= 8 bits/component or 16-bit gray accepted for JPEG-LS\n");
00230         return -1;
00231     }
00232     s->nb_components = nb_components;
00233     s->h_max = 1;
00234     s->v_max = 1;
00235     for(i=0;i<nb_components;i++) {
00236         /* component id */
00237         s->component_id[i] = get_bits(&s->gb, 8) - 1;
00238         s->h_count[i] = get_bits(&s->gb, 4);
00239         s->v_count[i] = get_bits(&s->gb, 4);
00240         /* compute hmax and vmax (only used in interleaved case) */
00241         if (s->h_count[i] > s->h_max)
00242             s->h_max = s->h_count[i];
00243         if (s->v_count[i] > s->v_max)
00244             s->v_max = s->v_count[i];
00245         s->quant_index[i] = get_bits(&s->gb, 8);
00246         if (s->quant_index[i] >= 4)
00247             return -1;
00248         av_log(s->avctx, AV_LOG_DEBUG, "component %d %d:%d id: %d quant:%d\n", i, s->h_count[i],
00249                s->v_count[i], s->component_id[i], s->quant_index[i]);
00250     }
00251 
00252     if(s->ls && (s->h_max > 1 || s->v_max > 1)) {
00253         av_log(s->avctx, AV_LOG_ERROR, "Subsampling in JPEG-LS is not supported.\n");
00254         return -1;
00255     }
00256 
00257     if(s->v_max==1 && s->h_max==1 && s->lossless==1) s->rgb=1;
00258 
00259     /* if different size, realloc/alloc picture */
00260     /* XXX: also check h_count and v_count */
00261     if (width != s->width || height != s->height) {
00262         av_freep(&s->qscale_table);
00263 
00264         s->width = width;
00265         s->height = height;
00266         s->interlaced = 0;
00267 
00268         /* test interlaced mode */
00269         if (s->first_picture &&
00270             s->org_height != 0 &&
00271             s->height < ((s->org_height * 3) / 4)) {
00272             s->interlaced = 1;
00273             s->bottom_field = s->interlace_polarity;
00274             s->picture.interlaced_frame = 1;
00275             s->picture.top_field_first = !s->interlace_polarity;
00276             height *= 2;
00277         }
00278 
00279         avcodec_set_dimensions(s->avctx, width, height);
00280 
00281         s->qscale_table= av_mallocz((s->width+15)/16);
00282 
00283         s->first_picture = 0;
00284     }
00285 
00286     if(s->interlaced && (s->bottom_field == !s->interlace_polarity))
00287         return 0;
00288 
00289     /* XXX: not complete test ! */
00290     pix_fmt_id = (s->h_count[0] << 28) | (s->v_count[0] << 24) |
00291                  (s->h_count[1] << 20) | (s->v_count[1] << 16) |
00292                  (s->h_count[2] << 12) | (s->v_count[2] <<  8) |
00293                  (s->h_count[3] <<  4) |  s->v_count[3];
00294     av_log(s->avctx, AV_LOG_DEBUG, "pix fmt id %x\n", pix_fmt_id);
00295     //NOTE we do not allocate pictures large enough for the possible padding of h/v_count being 4
00296     if(!(pix_fmt_id & 0xD0D0D0D0))
00297         pix_fmt_id-= (pix_fmt_id & 0xF0F0F0F0)>>1;
00298     if(!(pix_fmt_id & 0x0D0D0D0D))
00299         pix_fmt_id-= (pix_fmt_id & 0x0F0F0F0F)>>1;
00300 
00301     switch(pix_fmt_id){
00302     case 0x11111100:
00303         if(s->rgb){
00304             s->avctx->pix_fmt = PIX_FMT_BGRA;
00305         }else
00306             s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV444P : PIX_FMT_YUVJ444P;
00307         assert(s->nb_components==3);
00308         break;
00309     case 0x11000000:
00310         s->avctx->pix_fmt = PIX_FMT_GRAY8;
00311         break;
00312     case 0x12111100:
00313         s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV440P : PIX_FMT_YUVJ440P;
00314         break;
00315     case 0x21111100:
00316         s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV422P : PIX_FMT_YUVJ422P;
00317         break;
00318     case 0x22111100:
00319         s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV420P : PIX_FMT_YUVJ420P;
00320         break;
00321     default:
00322         av_log(s->avctx, AV_LOG_ERROR, "Unhandled pixel format 0x%x\n", pix_fmt_id);
00323         return -1;
00324     }
00325     if(s->ls){
00326         if(s->nb_components > 1)
00327             s->avctx->pix_fmt = PIX_FMT_RGB24;
00328         else if(s->bits <= 8)
00329             s->avctx->pix_fmt = PIX_FMT_GRAY8;
00330         else
00331             s->avctx->pix_fmt = PIX_FMT_GRAY16;
00332     }
00333 
00334     if(s->picture.data[0])
00335         s->avctx->release_buffer(s->avctx, &s->picture);
00336 
00337     s->picture.reference= 0;
00338     if(s->avctx->get_buffer(s->avctx, &s->picture) < 0){
00339         av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00340         return -1;
00341     }
00342     s->picture.pict_type= FF_I_TYPE;
00343     s->picture.key_frame= 1;
00344     s->got_picture = 1;
00345 
00346     for(i=0; i<3; i++){
00347         s->linesize[i]= s->picture.linesize[i] << s->interlaced;
00348     }
00349 
00350 //    printf("%d %d %d %d %d %d\n", s->width, s->height, s->linesize[0], s->linesize[1], s->interlaced, s->avctx->height);
00351 
00352     if (len != (8+(3*nb_components)))
00353     {
00354         av_log(s->avctx, AV_LOG_DEBUG, "decode_sof0: error, len(%d) mismatch\n", len);
00355     }
00356 
00357     /* totally blank picture as progressive JPEG will only add details to it */
00358     if(s->progressive){
00359         int bw = (width  + s->h_max*8-1) / (s->h_max*8);
00360         int bh = (height + s->v_max*8-1) / (s->v_max*8);
00361         for(i=0; i<s->nb_components; i++) {
00362             int size = bw * bh * s->h_count[i] * s->v_count[i];
00363             av_freep(&s->blocks[i]);
00364             av_freep(&s->last_nnz[i]);
00365             s->blocks[i] = av_malloc(size * sizeof(**s->blocks));
00366             s->last_nnz[i] = av_mallocz(size * sizeof(**s->last_nnz));
00367             s->block_stride[i] = bw * s->h_count[i];
00368         }
00369         memset(s->coefs_finished, 0, sizeof(s->coefs_finished));
00370     }
00371     return 0;
00372 }
00373 
00374 static inline int mjpeg_decode_dc(MJpegDecodeContext *s, int dc_index)
00375 {
00376     int code;
00377     code = get_vlc2(&s->gb, s->vlcs[0][dc_index].table, 9, 2);
00378     if (code < 0)
00379     {
00380         av_log(s->avctx, AV_LOG_WARNING, "mjpeg_decode_dc: bad vlc: %d:%d (%p)\n", 0, dc_index,
00381                &s->vlcs[0][dc_index]);
00382         return 0xffff;
00383     }
00384 
00385     if(code)
00386         return get_xbits(&s->gb, code);
00387     else
00388         return 0;
00389 }
00390 
00391 /* decode block and dequantize */
00392 static int decode_block(MJpegDecodeContext *s, DCTELEM *block,
00393                         int component, int dc_index, int ac_index, int16_t *quant_matrix)
00394 {
00395     int code, i, j, level, val;
00396 
00397     /* DC coef */
00398     val = mjpeg_decode_dc(s, dc_index);
00399     if (val == 0xffff) {
00400         av_log(s->avctx, AV_LOG_ERROR, "error dc\n");
00401         return -1;
00402     }
00403     val = val * quant_matrix[0] + s->last_dc[component];
00404     s->last_dc[component] = val;
00405     block[0] = val;
00406     /* AC coefs */
00407     i = 0;
00408     {OPEN_READER(re, &s->gb)
00409     for(;;) {
00410         UPDATE_CACHE(re, &s->gb);
00411         GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2)
00412 
00413         /* EOB */
00414         if (code == 0x10)
00415             break;
00416         i += ((unsigned)code) >> 4;
00417         if(code != 0x100){
00418             code &= 0xf;
00419             if(code > MIN_CACHE_BITS - 16){
00420                 UPDATE_CACHE(re, &s->gb)
00421             }
00422             {
00423                 int cache=GET_CACHE(re,&s->gb);
00424                 int sign=(~cache)>>31;
00425                 level = (NEG_USR32(sign ^ cache,code) ^ sign) - sign;
00426             }
00427 
00428             LAST_SKIP_BITS(re, &s->gb, code)
00429 
00430             if (i >= 63) {
00431                 if(i == 63){
00432                     j = s->scantable.permutated[63];
00433                     block[j] = level * quant_matrix[j];
00434                     break;
00435                 }
00436                 av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);
00437                 return -1;
00438             }
00439             j = s->scantable.permutated[i];
00440             block[j] = level * quant_matrix[j];
00441         }
00442     }
00443     CLOSE_READER(re, &s->gb)}
00444 
00445     return 0;
00446 }
00447 
00448 static int decode_dc_progressive(MJpegDecodeContext *s, DCTELEM *block, int component,
00449                                  int dc_index, int16_t *quant_matrix, int Al)
00450 {
00451     int val;
00452     s->dsp.clear_block(block);
00453     val = mjpeg_decode_dc(s, dc_index);
00454     if (val == 0xffff) {
00455         av_log(s->avctx, AV_LOG_ERROR, "error dc\n");
00456         return -1;
00457     }
00458     val = (val * quant_matrix[0] << Al) + s->last_dc[component];
00459     s->last_dc[component] = val;
00460     block[0] = val;
00461     return 0;
00462 }
00463 
00464 /* decode block and dequantize - progressive JPEG version */
00465 static int decode_block_progressive(MJpegDecodeContext *s, DCTELEM *block, uint8_t *last_nnz,
00466                                     int ac_index, int16_t *quant_matrix,
00467                                     int ss, int se, int Al, int *EOBRUN)
00468 {
00469     int code, i, j, level, val, run;
00470 
00471     if(*EOBRUN){
00472         (*EOBRUN)--;
00473         return 0;
00474     }
00475     {OPEN_READER(re, &s->gb)
00476     for(i=ss;;i++) {
00477         UPDATE_CACHE(re, &s->gb);
00478         GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2)
00479         /* Progressive JPEG use AC coeffs from zero and this decoder sets offset 16 by default */
00480         code -= 16;
00481         if(code & 0xF) {
00482             i += ((unsigned) code) >> 4;
00483             code &= 0xf;
00484             if(code > MIN_CACHE_BITS - 16){
00485                 UPDATE_CACHE(re, &s->gb)
00486             }
00487             {
00488                 int cache=GET_CACHE(re,&s->gb);
00489                 int sign=(~cache)>>31;
00490                 level = (NEG_USR32(sign ^ cache,code) ^ sign) - sign;
00491             }
00492 
00493             LAST_SKIP_BITS(re, &s->gb, code)
00494 
00495             if (i >= se) {
00496                 if(i == se){
00497                     j = s->scantable.permutated[se];
00498                     block[j] = level * quant_matrix[j] << Al;
00499                     break;
00500                 }
00501                 av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);
00502                 return -1;
00503             }
00504             j = s->scantable.permutated[i];
00505             block[j] = level * quant_matrix[j] << Al;
00506         }else{
00507             run = ((unsigned) code) >> 4;
00508             if(run == 0xF){// ZRL - skip 15 coefficients
00509                 i += 15;
00510             }else{
00511                 val = run;
00512                 run = (1 << run);
00513                 UPDATE_CACHE(re, &s->gb);
00514                 run += (GET_CACHE(re, &s->gb) >> (32 - val)) & (run - 1);
00515                 if(val)
00516                     LAST_SKIP_BITS(re, &s->gb, val);
00517                 *EOBRUN = run - 1;
00518                 break;
00519             }
00520         }
00521     }
00522     CLOSE_READER(re, &s->gb)}
00523     if(i > *last_nnz)
00524         *last_nnz = i;
00525     return 0;
00526 }
00527 
00528 #define REFINE_BIT(j) {\
00529     UPDATE_CACHE(re, &s->gb);\
00530     sign = block[j]>>15;\
00531     block[j] += SHOW_UBITS(re, &s->gb, 1) * ((quant_matrix[j]^sign)-sign) << Al;\
00532     LAST_SKIP_BITS(re, &s->gb, 1);\
00533 }
00534 
00535 #define ZERO_RUN \
00536 for(;;i++) {\
00537     if(i > last) {\
00538         i += run;\
00539         if(i > se) {\
00540             av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);\
00541             return -1;\
00542         }\
00543         break;\
00544     }\
00545     j = s->scantable.permutated[i];\
00546     if(block[j])\
00547         REFINE_BIT(j)\
00548     else if(run-- == 0)\
00549         break;\
00550 }
00551 
00552 /* decode block and dequantize - progressive JPEG refinement pass */
00553 static int decode_block_refinement(MJpegDecodeContext *s, DCTELEM *block, uint8_t *last_nnz,
00554                         int ac_index, int16_t *quant_matrix,
00555                         int ss, int se, int Al, int *EOBRUN)
00556 {
00557     int code, i=ss, j, sign, val, run;
00558     int last = FFMIN(se, *last_nnz);
00559 
00560     OPEN_READER(re, &s->gb);
00561     if(*EOBRUN)
00562         (*EOBRUN)--;
00563     else {
00564         for(;;i++) {
00565             UPDATE_CACHE(re, &s->gb);
00566             GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2)
00567             /* Progressive JPEG use AC coeffs from zero and this decoder sets offset 16 by default */
00568             code -= 16;
00569             if(code & 0xF) {
00570                 run = ((unsigned) code) >> 4;
00571                 UPDATE_CACHE(re, &s->gb);
00572                 val = SHOW_UBITS(re, &s->gb, 1);
00573                 LAST_SKIP_BITS(re, &s->gb, 1);
00574                 ZERO_RUN;
00575                 j = s->scantable.permutated[i];
00576                 val--;
00577                 block[j] = ((quant_matrix[j]^val)-val) << Al;
00578                 if(i == se) {
00579                     if(i > *last_nnz)
00580                         *last_nnz = i;
00581                     CLOSE_READER(re, &s->gb)
00582                     return 0;
00583                 }
00584             }else{
00585                 run = ((unsigned) code) >> 4;
00586                 if(run == 0xF){
00587                     ZERO_RUN;
00588                 }else{
00589                     val = run;
00590                     run = (1 << run);
00591                     if(val) {
00592                         UPDATE_CACHE(re, &s->gb);
00593                         run += SHOW_UBITS(re, &s->gb, val);
00594                         LAST_SKIP_BITS(re, &s->gb, val);
00595                     }
00596                     *EOBRUN = run - 1;
00597                     break;
00598                 }
00599             }
00600         }
00601 
00602         if(i > *last_nnz)
00603             *last_nnz = i;
00604     }
00605 
00606     for(;i<=last;i++) {
00607         j = s->scantable.permutated[i];
00608         if(block[j])
00609             REFINE_BIT(j)
00610     }
00611     CLOSE_READER(re, &s->gb);
00612 
00613     return 0;
00614 }
00615 #undef REFINE_BIT
00616 #undef ZERO_RUN
00617 
00618 static int ljpeg_decode_rgb_scan(MJpegDecodeContext *s, int predictor, int point_transform){
00619     int i, mb_x, mb_y;
00620     uint16_t (*buffer)[4];
00621     int left[3], top[3], topleft[3];
00622     const int linesize= s->linesize[0];
00623     const int mask= (1<<s->bits)-1;
00624 
00625     av_fast_malloc(&s->ljpeg_buffer, &s->ljpeg_buffer_size, (unsigned)s->mb_width * 4 * sizeof(s->ljpeg_buffer[0][0]));
00626     buffer= s->ljpeg_buffer;
00627 
00628     for(i=0; i<3; i++){
00629         buffer[0][i]= 1 << (s->bits + point_transform - 1);
00630     }
00631     for(mb_y = 0; mb_y < s->mb_height; mb_y++) {
00632         const int modified_predictor= mb_y ? predictor : 1;
00633         uint8_t *ptr = s->picture.data[0] + (linesize * mb_y);
00634 
00635         if (s->interlaced && s->bottom_field)
00636             ptr += linesize >> 1;
00637 
00638         for(i=0; i<3; i++){
00639             top[i]= left[i]= topleft[i]= buffer[0][i];
00640         }
00641         for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
00642             if (s->restart_interval && !s->restart_count)
00643                 s->restart_count = s->restart_interval;
00644 
00645             for(i=0;i<3;i++) {
00646                 int pred;
00647 
00648                 topleft[i]= top[i];
00649                 top[i]= buffer[mb_x][i];
00650 
00651                 PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
00652 
00653                 left[i]=
00654                 buffer[mb_x][i]= mask & (pred + (mjpeg_decode_dc(s, s->dc_index[i]) << point_transform));
00655             }
00656 
00657             if (s->restart_interval && !--s->restart_count) {
00658                 align_get_bits(&s->gb);
00659                 skip_bits(&s->gb, 16); /* skip RSTn */
00660             }
00661         }
00662 
00663         if(s->rct){
00664             for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
00665                 ptr[4*mb_x+1] = buffer[mb_x][0] - ((buffer[mb_x][1] + buffer[mb_x][2] - 0x200)>>2);
00666                 ptr[4*mb_x+0] = buffer[mb_x][1] + ptr[4*mb_x+1];
00667                 ptr[4*mb_x+2] = buffer[mb_x][2] + ptr[4*mb_x+1];
00668             }
00669         }else if(s->pegasus_rct){
00670             for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
00671                 ptr[4*mb_x+1] = buffer[mb_x][0] - ((buffer[mb_x][1] + buffer[mb_x][2])>>2);
00672                 ptr[4*mb_x+0] = buffer[mb_x][1] + ptr[4*mb_x+1];
00673                 ptr[4*mb_x+2] = buffer[mb_x][2] + ptr[4*mb_x+1];
00674             }
00675         }else{
00676             for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
00677                 ptr[4*mb_x+0] = buffer[mb_x][2];
00678                 ptr[4*mb_x+1] = buffer[mb_x][1];
00679                 ptr[4*mb_x+2] = buffer[mb_x][0];
00680             }
00681         }
00682     }
00683     return 0;
00684 }
00685 
00686 static int ljpeg_decode_yuv_scan(MJpegDecodeContext *s, int predictor, int point_transform){
00687     int i, mb_x, mb_y;
00688     const int nb_components=3;
00689 
00690     for(mb_y = 0; mb_y < s->mb_height; mb_y++) {
00691         for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
00692             if (s->restart_interval && !s->restart_count)
00693                 s->restart_count = s->restart_interval;
00694 
00695             if(mb_x==0 || mb_y==0 || s->interlaced){
00696                 for(i=0;i<nb_components;i++) {
00697                     uint8_t *ptr;
00698                     int n, h, v, x, y, c, j, linesize;
00699                     n = s->nb_blocks[i];
00700                     c = s->comp_index[i];
00701                     h = s->h_scount[i];
00702                     v = s->v_scount[i];
00703                     x = 0;
00704                     y = 0;
00705                     linesize= s->linesize[c];
00706 
00707                     for(j=0; j<n; j++) {
00708                         int pred;
00709 
00710                         ptr = s->picture.data[c] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
00711                         if(y==0 && mb_y==0){
00712                             if(x==0 && mb_x==0){
00713                                 pred= 128 << point_transform;
00714                             }else{
00715                                 pred= ptr[-1];
00716                             }
00717                         }else{
00718                             if(x==0 && mb_x==0){
00719                                 pred= ptr[-linesize];
00720                             }else{
00721                                 PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
00722                             }
00723                         }
00724 
00725                         if (s->interlaced && s->bottom_field)
00726                             ptr += linesize >> 1;
00727                         *ptr= pred + (mjpeg_decode_dc(s, s->dc_index[i]) << point_transform);
00728 
00729                         if (++x == h) {
00730                             x = 0;
00731                             y++;
00732                         }
00733                     }
00734                 }
00735             }else{
00736                 for(i=0;i<nb_components;i++) {
00737                     uint8_t *ptr;
00738                     int n, h, v, x, y, c, j, linesize;
00739                     n = s->nb_blocks[i];
00740                     c = s->comp_index[i];
00741                     h = s->h_scount[i];
00742                     v = s->v_scount[i];
00743                     x = 0;
00744                     y = 0;
00745                     linesize= s->linesize[c];
00746 
00747                     for(j=0; j<n; j++) {
00748                         int pred;
00749 
00750                         ptr = s->picture.data[c] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
00751                         PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
00752                         *ptr= pred + (mjpeg_decode_dc(s, s->dc_index[i]) << point_transform);
00753                         if (++x == h) {
00754                             x = 0;
00755                             y++;
00756                         }
00757                     }
00758                 }
00759             }
00760             if (s->restart_interval && !--s->restart_count) {
00761                 align_get_bits(&s->gb);
00762                 skip_bits(&s->gb, 16); /* skip RSTn */
00763             }
00764         }
00765     }
00766     return 0;
00767 }
00768 
00769 static int mjpeg_decode_scan(MJpegDecodeContext *s, int nb_components, int Ah, int Al){
00770     int i, mb_x, mb_y;
00771     uint8_t* data[MAX_COMPONENTS];
00772     int linesize[MAX_COMPONENTS];
00773 
00774     if(s->flipped && s->avctx->flags & CODEC_FLAG_EMU_EDGE) {
00775         av_log(s->avctx, AV_LOG_ERROR, "Can not flip image with CODEC_FLAG_EMU_EDGE set!\n");
00776         s->flipped = 0;
00777     }
00778     for(i=0; i < nb_components; i++) {
00779         int c = s->comp_index[i];
00780         data[c] = s->picture.data[c];
00781         linesize[c]=s->linesize[c];
00782         s->coefs_finished[c] |= 1;
00783         if(s->flipped) {
00784             //picture should be flipped upside-down for this codec
00785             data[c] += (linesize[c] * (s->v_scount[i] * (8 * s->mb_height -((s->height/s->v_max)&7)) - 1 ));
00786             linesize[c] *= -1;
00787         }
00788     }
00789 
00790     for(mb_y = 0; mb_y < s->mb_height; mb_y++) {
00791         for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
00792             if (s->restart_interval && !s->restart_count)
00793                 s->restart_count = s->restart_interval;
00794 
00795             if(get_bits_count(&s->gb)>s->gb.size_in_bits){
00796                 av_log(s->avctx, AV_LOG_ERROR, "overread %d\n", get_bits_count(&s->gb) - s->gb.size_in_bits);
00797                 return -1;
00798             }
00799             for(i=0;i<nb_components;i++) {
00800                 uint8_t *ptr;
00801                 int n, h, v, x, y, c, j;
00802                 n = s->nb_blocks[i];
00803                 c = s->comp_index[i];
00804                 h = s->h_scount[i];
00805                 v = s->v_scount[i];
00806                 x = 0;
00807                 y = 0;
00808                 for(j=0;j<n;j++) {
00809                     ptr = data[c] +
00810                         (((linesize[c] * (v * mb_y + y) * 8) +
00811                         (h * mb_x + x) * 8) >> s->avctx->lowres);
00812                     if(s->interlaced && s->bottom_field)
00813                         ptr += linesize[c] >> 1;
00814                     if(!s->progressive) {
00815                         s->dsp.clear_block(s->block);
00816                         if(decode_block(s, s->block, i,
00817                                      s->dc_index[i], s->ac_index[i],
00818                                      s->quant_matrixes[ s->quant_index[c] ]) < 0) {
00819                             av_log(s->avctx, AV_LOG_ERROR, "error y=%d x=%d\n", mb_y, mb_x);
00820                             return -1;
00821                         }
00822                         s->dsp.idct_put(ptr, linesize[c], s->block);
00823                     } else {
00824                         int block_idx = s->block_stride[c] * (v * mb_y + y) + (h * mb_x + x);
00825                         DCTELEM *block = s->blocks[c][block_idx];
00826                         if(Ah)
00827                             block[0] += get_bits1(&s->gb) * s->quant_matrixes[ s->quant_index[c] ][0] << Al;
00828                         else if(decode_dc_progressive(s, block, i, s->dc_index[i], s->quant_matrixes[ s->quant_index[c] ], Al) < 0) {
00829                             av_log(s->avctx, AV_LOG_ERROR, "error y=%d x=%d\n", mb_y, mb_x);
00830                             return -1;
00831                         }
00832                     }
00833 //                    av_log(s->avctx, AV_LOG_DEBUG, "mb: %d %d processed\n", mb_y, mb_x);
00834 //av_log(NULL, AV_LOG_DEBUG, "%d %d %d %d %d %d %d %d \n", mb_x, mb_y, x, y, c, s->bottom_field, (v * mb_y + y) * 8, (h * mb_x + x) * 8);
00835                     if (++x == h) {
00836                         x = 0;
00837                         y++;
00838                     }
00839                 }
00840             }
00841 
00842             if (s->restart_interval && show_bits(&s->gb, 8) == 0xFF){ /* skip RSTn */
00843                 --s->restart_count;
00844                 align_get_bits(&s->gb);
00845                 while(show_bits(&s->gb, 8) == 0xFF)
00846                     skip_bits(&s->gb, 8);
00847                 skip_bits(&s->gb, 8);
00848                 for (i=0; i<nb_components; i++) /* reset dc */
00849                     s->last_dc[i] = 1024;
00850             }
00851         }
00852     }
00853     return 0;
00854 }
00855 
00856 static int mjpeg_decode_scan_progressive_ac(MJpegDecodeContext *s, int ss, int se, int Ah, int Al){
00857     int mb_x, mb_y;
00858     int EOBRUN = 0;
00859     int c = s->comp_index[0];
00860     uint8_t* data = s->picture.data[c];
00861     int linesize = s->linesize[c];
00862     int last_scan = 0;
00863     int16_t *quant_matrix = s->quant_matrixes[ s->quant_index[c] ];
00864 
00865     if(!Al) {
00866         s->coefs_finished[c] |= (1LL<<(se+1))-(1LL<<ss);
00867         last_scan = !~s->coefs_finished[c];
00868     }
00869 
00870     if(s->interlaced && s->bottom_field)
00871         data += linesize >> 1;
00872 
00873     for(mb_y = 0; mb_y < s->mb_height; mb_y++) {
00874         uint8_t *ptr = data + (mb_y*linesize*8 >> s->avctx->lowres);
00875         int block_idx = mb_y * s->block_stride[c];
00876         DCTELEM (*block)[64] = &s->blocks[c][block_idx];
00877         uint8_t *last_nnz = &s->last_nnz[c][block_idx];
00878         for(mb_x = 0; mb_x < s->mb_width; mb_x++, block++, last_nnz++) {
00879             int ret;
00880             if(Ah)
00881                 ret = decode_block_refinement(s, *block, last_nnz, s->ac_index[0],
00882                                               quant_matrix, ss, se, Al, &EOBRUN);
00883             else
00884                 ret = decode_block_progressive(s, *block, last_nnz, s->ac_index[0],
00885                                                quant_matrix, ss, se, Al, &EOBRUN);
00886             if(ret < 0) {
00887                 av_log(s->avctx, AV_LOG_ERROR, "error y=%d x=%d\n", mb_y, mb_x);
00888                 return -1;
00889             }
00890             if(last_scan) {
00891                 s->dsp.idct_put(ptr, linesize, *block);
00892                 ptr += 8 >> s->avctx->lowres;
00893             }
00894         }
00895     }
00896     return 0;
00897 }
00898 
00899 int ff_mjpeg_decode_sos(MJpegDecodeContext *s)
00900 {
00901     int len, nb_components, i, h, v, predictor, point_transform;
00902     int index, id;
00903     const int block_size= s->lossless ? 1 : 8;
00904     int ilv, prev_shift;
00905 
00906     /* XXX: verify len field validity */
00907     len = get_bits(&s->gb, 16);
00908     nb_components = get_bits(&s->gb, 8);
00909     if (nb_components == 0 || nb_components > MAX_COMPONENTS){
00910         av_log(s->avctx, AV_LOG_ERROR, "decode_sos: nb_components (%d) unsupported\n", nb_components);
00911         return -1;
00912     }
00913     if (len != 6+2*nb_components)
00914     {
00915         av_log(s->avctx, AV_LOG_ERROR, "decode_sos: invalid len (%d)\n", len);
00916         return -1;
00917     }
00918     for(i=0;i<nb_components;i++) {
00919         id = get_bits(&s->gb, 8) - 1;
00920         av_log(s->avctx, AV_LOG_DEBUG, "component: %d\n", id);
00921         /* find component index */
00922         for(index=0;index<s->nb_components;index++)
00923             if (id == s->component_id[index])
00924                 break;
00925         if (index == s->nb_components)
00926         {
00927             av_log(s->avctx, AV_LOG_ERROR, "decode_sos: index(%d) out of components\n", index);
00928             return -1;
00929         }
00930         /* Metasoft MJPEG codec has Cb and Cr swapped */
00931         if (s->avctx->codec_tag == MKTAG('M', 'T', 'S', 'J')
00932             && nb_components == 3 && s->nb_components == 3 && i)
00933             index = 3 - i;
00934 
00935         s->comp_index[i] = index;
00936 
00937         s->nb_blocks[i] = s->h_count[index] * s->v_count[index];
00938         s->h_scount[i] = s->h_count[index];
00939         s->v_scount[i] = s->v_count[index];
00940 
00941         s->dc_index[i] = get_bits(&s->gb, 4);
00942         s->ac_index[i] = get_bits(&s->gb, 4);
00943 
00944         if (s->dc_index[i] <  0 || s->ac_index[i] < 0 ||
00945             s->dc_index[i] >= 4 || s->ac_index[i] >= 4)
00946             goto out_of_range;
00947         if (!s->vlcs[0][s->dc_index[i]].table || !s->vlcs[1][s->ac_index[i]].table)
00948             goto out_of_range;
00949     }
00950 
00951     predictor= get_bits(&s->gb, 8); /* JPEG Ss / lossless JPEG predictor /JPEG-LS NEAR */
00952     ilv= get_bits(&s->gb, 8);    /* JPEG Se / JPEG-LS ILV */
00953     prev_shift = get_bits(&s->gb, 4); /* Ah */
00954     point_transform= get_bits(&s->gb, 4); /* Al */
00955 
00956     for(i=0;i<nb_components;i++)
00957         s->last_dc[i] = 1024;
00958 
00959     if (nb_components > 1) {
00960         /* interleaved stream */
00961         s->mb_width  = (s->width  + s->h_max * block_size - 1) / (s->h_max * block_size);
00962         s->mb_height = (s->height + s->v_max * block_size - 1) / (s->v_max * block_size);
00963     } else if(!s->ls) { /* skip this for JPEG-LS */
00964         h = s->h_max / s->h_scount[0];
00965         v = s->v_max / s->v_scount[0];
00966         s->mb_width  = (s->width  + h * block_size - 1) / (h * block_size);
00967         s->mb_height = (s->height + v * block_size - 1) / (v * block_size);
00968         s->nb_blocks[0] = 1;
00969         s->h_scount[0] = 1;
00970         s->v_scount[0] = 1;
00971     }
00972 
00973     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
00974         av_log(s->avctx, AV_LOG_DEBUG, "%s %s p:%d >>:%d ilv:%d bits:%d %s\n", s->lossless ? "lossless" : "sequential DCT", s->rgb ? "RGB" : "",
00975                predictor, point_transform, ilv, s->bits,
00976                s->pegasus_rct ? "PRCT" : (s->rct ? "RCT" : ""));
00977 
00978 
00979     /* mjpeg-b can have padding bytes between sos and image data, skip them */
00980     for (i = s->mjpb_skiptosod; i > 0; i--)
00981         skip_bits(&s->gb, 8);
00982 
00983     if(s->lossless){
00984         if(CONFIG_JPEGLS_DECODER && s->ls){
00985 //            for(){
00986 //            reset_ls_coding_parameters(s, 0);
00987 
00988             if(ff_jpegls_decode_picture(s, predictor, point_transform, ilv) < 0)
00989                 return -1;
00990         }else{
00991             if(s->rgb){
00992                 if(ljpeg_decode_rgb_scan(s, predictor, point_transform) < 0)
00993                     return -1;
00994             }else{
00995                 if(ljpeg_decode_yuv_scan(s, predictor, point_transform) < 0)
00996                     return -1;
00997             }
00998         }
00999     }else{
01000         if(s->progressive && predictor) {
01001             if(mjpeg_decode_scan_progressive_ac(s, predictor, ilv, prev_shift, point_transform) < 0)
01002                 return -1;
01003         } else {
01004             if(mjpeg_decode_scan(s, nb_components, prev_shift, point_transform) < 0)
01005                 return -1;
01006         }
01007     }
01008     emms_c();
01009     return 0;
01010  out_of_range:
01011     av_log(s->avctx, AV_LOG_ERROR, "decode_sos: ac/dc index out of range\n");
01012     return -1;
01013 }
01014 
01015 static int mjpeg_decode_dri(MJpegDecodeContext *s)
01016 {
01017     if (get_bits(&s->gb, 16) != 4)
01018         return -1;
01019     s->restart_interval = get_bits(&s->gb, 16);
01020     s->restart_count = 0;
01021     av_log(s->avctx, AV_LOG_DEBUG, "restart interval: %d\n", s->restart_interval);
01022 
01023     return 0;
01024 }
01025 
01026 static int mjpeg_decode_app(MJpegDecodeContext *s)
01027 {
01028     int len, id, i;
01029 
01030     len = get_bits(&s->gb, 16);
01031     if (len < 5)
01032         return -1;
01033     if(8*len + get_bits_count(&s->gb) > s->gb.size_in_bits)
01034         return -1;
01035 
01036     id = (get_bits(&s->gb, 16) << 16) | get_bits(&s->gb, 16);
01037     id = be2me_32(id);
01038     len -= 6;
01039 
01040     if(s->avctx->debug & FF_DEBUG_STARTCODE){
01041         av_log(s->avctx, AV_LOG_DEBUG, "APPx %8X\n", id);
01042     }
01043 
01044     /* buggy AVID, it puts EOI only at every 10th frame */
01045     /* also this fourcc is used by non-avid files too, it holds some
01046        informations, but it's always present in AVID creates files */
01047     if (id == AV_RL32("AVI1"))
01048     {
01049         /* structure:
01050             4bytes      AVI1
01051             1bytes      polarity
01052             1bytes      always zero
01053             4bytes      field_size
01054             4bytes      field_size_less_padding
01055         */
01056             s->buggy_avid = 1;
01057 //        if (s->first_picture)
01058 //            printf("mjpeg: workarounding buggy AVID\n");
01059         i = get_bits(&s->gb, 8);
01060         if     (i==2) s->bottom_field= 1;
01061         else if(i==1) s->bottom_field= 0;
01062 #if 0
01063         skip_bits(&s->gb, 8);
01064         skip_bits(&s->gb, 32);
01065         skip_bits(&s->gb, 32);
01066         len -= 10;
01067 #endif
01068 //        if (s->interlace_polarity)
01069 //            printf("mjpeg: interlace polarity: %d\n", s->interlace_polarity);
01070         goto out;
01071     }
01072 
01073 //    len -= 2;
01074 
01075     if (id == AV_RL32("JFIF"))
01076     {
01077         int t_w, t_h, v1, v2;
01078         skip_bits(&s->gb, 8); /* the trailing zero-byte */
01079         v1= get_bits(&s->gb, 8);
01080         v2= get_bits(&s->gb, 8);
01081         skip_bits(&s->gb, 8);
01082 
01083         s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 16);
01084         s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 16);
01085 
01086         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01087             av_log(s->avctx, AV_LOG_INFO, "mjpeg: JFIF header found (version: %x.%x) SAR=%d/%d\n",
01088                 v1, v2,
01089                 s->avctx->sample_aspect_ratio.num,
01090                 s->avctx->sample_aspect_ratio.den
01091             );
01092 
01093         t_w = get_bits(&s->gb, 8);
01094         t_h = get_bits(&s->gb, 8);
01095         if (t_w && t_h)
01096         {
01097             /* skip thumbnail */
01098             if (len-10-(t_w*t_h*3) > 0)
01099                 len -= t_w*t_h*3;
01100         }
01101         len -= 10;
01102         goto out;
01103     }
01104 
01105     if (id == AV_RL32("Adob") && (get_bits(&s->gb, 8) == 'e'))
01106     {
01107         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01108             av_log(s->avctx, AV_LOG_INFO, "mjpeg: Adobe header found\n");
01109         skip_bits(&s->gb, 16); /* version */
01110         skip_bits(&s->gb, 16); /* flags0 */
01111         skip_bits(&s->gb, 16); /* flags1 */
01112         skip_bits(&s->gb, 8);  /* transform */
01113         len -= 7;
01114         goto out;
01115     }
01116 
01117     if (id == AV_RL32("LJIF")){
01118         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01119             av_log(s->avctx, AV_LOG_INFO, "Pegasus lossless jpeg header found\n");
01120         skip_bits(&s->gb, 16); /* version ? */
01121         skip_bits(&s->gb, 16); /* unknwon always 0? */
01122         skip_bits(&s->gb, 16); /* unknwon always 0? */
01123         skip_bits(&s->gb, 16); /* unknwon always 0? */
01124         switch( get_bits(&s->gb, 8)){
01125         case 1:
01126             s->rgb= 1;
01127             s->pegasus_rct=0;
01128             break;
01129         case 2:
01130             s->rgb= 1;
01131             s->pegasus_rct=1;
01132             break;
01133         default:
01134             av_log(s->avctx, AV_LOG_ERROR, "unknown colorspace\n");
01135         }
01136         len -= 9;
01137         goto out;
01138     }
01139 
01140     /* Apple MJPEG-A */
01141     if ((s->start_code == APP1) && (len > (0x28 - 8)))
01142     {
01143         id = (get_bits(&s->gb, 16) << 16) | get_bits(&s->gb, 16);
01144         id = be2me_32(id);
01145         len -= 4;
01146         if (id == AV_RL32("mjpg")) /* Apple MJPEG-A */
01147         {
01148 #if 0
01149             skip_bits(&s->gb, 32); /* field size */
01150             skip_bits(&s->gb, 32); /* pad field size */
01151             skip_bits(&s->gb, 32); /* next off */
01152             skip_bits(&s->gb, 32); /* quant off */
01153             skip_bits(&s->gb, 32); /* huff off */
01154             skip_bits(&s->gb, 32); /* image off */
01155             skip_bits(&s->gb, 32); /* scan off */
01156             skip_bits(&s->gb, 32); /* data off */
01157 #endif
01158             if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01159                 av_log(s->avctx, AV_LOG_INFO, "mjpeg: Apple MJPEG-A header found\n");
01160         }
01161     }
01162 
01163 out:
01164     /* slow but needed for extreme adobe jpegs */
01165     if (len < 0)
01166         av_log(s->avctx, AV_LOG_ERROR, "mjpeg: error, decode_app parser read over the end\n");
01167     while(--len > 0)
01168         skip_bits(&s->gb, 8);
01169 
01170     return 0;
01171 }
01172 
01173 static int mjpeg_decode_com(MJpegDecodeContext *s)
01174 {
01175     int len = get_bits(&s->gb, 16);
01176     if (len >= 2 && 8*len - 16 + get_bits_count(&s->gb) <= s->gb.size_in_bits) {
01177         char *cbuf = av_malloc(len - 1);
01178         if (cbuf) {
01179             int i;
01180             for (i = 0; i < len - 2; i++)
01181                 cbuf[i] = get_bits(&s->gb, 8);
01182             if (i > 0 && cbuf[i-1] == '\n')
01183                 cbuf[i-1] = 0;
01184             else
01185                 cbuf[i] = 0;
01186 
01187             if(s->avctx->debug & FF_DEBUG_PICT_INFO)
01188                 av_log(s->avctx, AV_LOG_INFO, "mjpeg comment: '%s'\n", cbuf);
01189 
01190             /* buggy avid, it puts EOI only at every 10th frame */
01191             if (!strcmp(cbuf, "AVID"))
01192             {
01193                 s->buggy_avid = 1;
01194                 //        if (s->first_picture)
01195                 //            printf("mjpeg: workarounding buggy AVID\n");
01196             }
01197             else if(!strcmp(cbuf, "CS=ITU601")){
01198                 s->cs_itu601= 1;
01199             }
01200             else if((len > 20 && !strncmp(cbuf, "Intel(R) JPEG Library", 21)) ||
01201                     (len > 19 && !strncmp(cbuf, "Metasoft MJPEG Codec", 20))){
01202                 s->flipped = 1;
01203             }
01204 
01205             av_free(cbuf);
01206         }
01207     }
01208 
01209     return 0;
01210 }
01211 
01212 #if 0
01213 static int valid_marker_list[] =
01214 {
01215         /* 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f */
01216 /* 0 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01217 /* 1 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01218 /* 2 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01219 /* 3 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01220 /* 4 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01221 /* 5 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01222 /* 6 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01223 /* 7 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01224 /* 8 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01225 /* 9 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01226 /* a */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01227 /* b */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
01228 /* c */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
01229 /* d */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
01230 /* e */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
01231 /* f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,
01232 }
01233 #endif
01234 
01235 /* return the 8 bit start code value and update the search
01236    state. Return -1 if no start code found */
01237 static int find_marker(const uint8_t **pbuf_ptr, const uint8_t *buf_end)
01238 {
01239     const uint8_t *buf_ptr;
01240     unsigned int v, v2;
01241     int val;
01242 #ifdef DEBUG
01243     int skipped=0;
01244 #endif
01245 
01246     buf_ptr = *pbuf_ptr;
01247     while (buf_ptr < buf_end) {
01248         v = *buf_ptr++;
01249         v2 = *buf_ptr;
01250         if ((v == 0xff) && (v2 >= 0xc0) && (v2 <= 0xfe) && buf_ptr < buf_end) {
01251             val = *buf_ptr++;
01252             goto found;
01253         }
01254 #ifdef DEBUG
01255         skipped++;
01256 #endif
01257     }
01258     val = -1;
01259 found:
01260     dprintf(NULL, "find_marker skipped %d bytes\n", skipped);
01261     *pbuf_ptr = buf_ptr;
01262     return val;
01263 }
01264 
01265 int ff_mjpeg_decode_frame(AVCodecContext *avctx,
01266                               void *data, int *data_size,
01267                               AVPacket *avpkt)
01268 {
01269     const uint8_t *buf = avpkt->data;
01270     int buf_size = avpkt->size;
01271     MJpegDecodeContext *s = avctx->priv_data;
01272     const uint8_t *buf_end, *buf_ptr;
01273     int start_code;
01274     AVFrame *picture = data;
01275 
01276     s->got_picture = 0; // picture from previous image can not be reused
01277     buf_ptr = buf;
01278     buf_end = buf + buf_size;
01279     while (buf_ptr < buf_end) {
01280         /* find start next marker */
01281         start_code = find_marker(&buf_ptr, buf_end);
01282         {
01283             /* EOF */
01284             if (start_code < 0) {
01285                 goto the_end;
01286             } else {
01287                 av_log(avctx, AV_LOG_DEBUG, "marker=%x avail_size_in_buf=%td\n", start_code, buf_end - buf_ptr);
01288 
01289                 if ((buf_end - buf_ptr) > s->buffer_size)
01290                 {
01291                     av_free(s->buffer);
01292                     s->buffer_size = buf_end-buf_ptr;
01293                     s->buffer = av_malloc(s->buffer_size + FF_INPUT_BUFFER_PADDING_SIZE);
01294                     av_log(avctx, AV_LOG_DEBUG, "buffer too small, expanding to %d bytes\n",
01295                         s->buffer_size);
01296                 }
01297 
01298                 /* unescape buffer of SOS, use special treatment for JPEG-LS */
01299                 if (start_code == SOS && !s->ls)
01300                 {
01301                     const uint8_t *src = buf_ptr;
01302                     uint8_t *dst = s->buffer;
01303 
01304                     while (src<buf_end)
01305                     {
01306                         uint8_t x = *(src++);
01307 
01308                         *(dst++) = x;
01309                         if (avctx->codec_id != CODEC_ID_THP)
01310                         {
01311                             if (x == 0xff) {
01312                                 while (src < buf_end && x == 0xff)
01313                                     x = *(src++);
01314 
01315                                 if (x >= 0xd0 && x <= 0xd7)
01316                                     *(dst++) = x;
01317                                 else if (x)
01318                                     break;
01319                             }
01320                         }
01321                     }
01322                     init_get_bits(&s->gb, s->buffer, (dst - s->buffer)*8);
01323 
01324                     av_log(avctx, AV_LOG_DEBUG, "escaping removed %td bytes\n",
01325                            (buf_end - buf_ptr) - (dst - s->buffer));
01326                 }
01327                 else if(start_code == SOS && s->ls){
01328                     const uint8_t *src = buf_ptr;
01329                     uint8_t *dst = s->buffer;
01330                     int bit_count = 0;
01331                     int t = 0, b = 0;
01332                     PutBitContext pb;
01333 
01334                     s->cur_scan++;
01335 
01336                     /* find marker */
01337                     while (src + t < buf_end){
01338                         uint8_t x = src[t++];
01339                         if (x == 0xff){
01340                             while((src + t < buf_end) && x == 0xff)
01341                                 x = src[t++];
01342                             if (x & 0x80) {
01343                                 t -= 2;
01344                                 break;
01345                             }
01346                         }
01347                     }
01348                     bit_count = t * 8;
01349 
01350                     init_put_bits(&pb, dst, t);
01351 
01352                     /* unescape bitstream */
01353                     while(b < t){
01354                         uint8_t x = src[b++];
01355                         put_bits(&pb, 8, x);
01356                         if(x == 0xFF){
01357                             x = src[b++];
01358                             put_bits(&pb, 7, x);
01359                             bit_count--;
01360                         }
01361                     }
01362                     flush_put_bits(&pb);
01363 
01364                     init_get_bits(&s->gb, dst, bit_count);
01365                 }
01366                 else
01367                     init_get_bits(&s->gb, buf_ptr, (buf_end - buf_ptr)*8);
01368 
01369                 s->start_code = start_code;
01370                 if(s->avctx->debug & FF_DEBUG_STARTCODE){
01371                     av_log(avctx, AV_LOG_DEBUG, "startcode: %X\n", start_code);
01372                 }
01373 
01374                 /* process markers */
01375                 if (start_code >= 0xd0 && start_code <= 0xd7) {
01376                     av_log(avctx, AV_LOG_DEBUG, "restart marker: %d\n", start_code&0x0f);
01377                     /* APP fields */
01378                 } else if (start_code >= APP0 && start_code <= APP15) {
01379                     mjpeg_decode_app(s);
01380                     /* Comment */
01381                 } else if (start_code == COM){
01382                     mjpeg_decode_com(s);
01383                 }
01384 
01385                 switch(start_code) {
01386                 case SOI:
01387                     s->restart_interval = 0;
01388 
01389                     s->restart_count = 0;
01390                     /* nothing to do on SOI */
01391                     break;
01392                 case DQT:
01393                     ff_mjpeg_decode_dqt(s);
01394                     break;
01395                 case DHT:
01396                     if(ff_mjpeg_decode_dht(s) < 0){
01397                         av_log(avctx, AV_LOG_ERROR, "huffman table decode error\n");
01398                         return -1;
01399                     }
01400                     break;
01401                 case SOF0:
01402                 case SOF1:
01403                     s->lossless=0;
01404                     s->ls=0;
01405                     s->progressive=0;
01406                     if (ff_mjpeg_decode_sof(s) < 0)
01407                         return -1;
01408                     break;
01409                 case SOF2:
01410                     s->lossless=0;
01411                     s->ls=0;
01412                     s->progressive=1;
01413                     if (ff_mjpeg_decode_sof(s) < 0)
01414                         return -1;
01415                     break;
01416                 case SOF3:
01417                     s->lossless=1;
01418                     s->ls=0;
01419                     s->progressive=0;
01420                     if (ff_mjpeg_decode_sof(s) < 0)
01421                         return -1;
01422                     break;
01423                 case SOF48:
01424                     s->lossless=1;
01425                     s->ls=1;
01426                     s->progressive=0;
01427                     if (ff_mjpeg_decode_sof(s) < 0)
01428                         return -1;
01429                     break;
01430                 case LSE:
01431                     if (!CONFIG_JPEGLS_DECODER || ff_jpegls_decode_lse(s) < 0)
01432                         return -1;
01433                     break;
01434                 case EOI:
01435                     s->cur_scan = 0;
01436                     if ((s->buggy_avid && !s->interlaced) || s->restart_interval)
01437                         break;
01438 eoi_parser:
01439                     if (!s->got_picture) {
01440                         av_log(avctx, AV_LOG_WARNING, "Found EOI before any SOF, ignoring\n");
01441                         break;
01442                     }
01443                     {
01444                         if (s->interlaced) {
01445                             s->bottom_field ^= 1;
01446                             /* if not bottom field, do not output image yet */
01447                             if (s->bottom_field == !s->interlace_polarity)
01448                                 goto not_the_end;
01449                         }
01450                         *picture = s->picture;
01451                         *data_size = sizeof(AVFrame);
01452 
01453                         if(!s->lossless){
01454                             picture->quality= FFMAX3(s->qscale[0], s->qscale[1], s->qscale[2]);
01455                             picture->qstride= 0;
01456                             picture->qscale_table= s->qscale_table;
01457                             memset(picture->qscale_table, picture->quality, (s->width+15)/16);
01458                             if(avctx->debug & FF_DEBUG_QP)
01459                                 av_log(avctx, AV_LOG_DEBUG, "QP: %d\n", picture->quality);
01460                             picture->quality*= FF_QP2LAMBDA;
01461                         }
01462 
01463                         goto the_end;
01464                     }
01465                     break;
01466                 case SOS:
01467                     if (!s->got_picture) {
01468                         av_log(avctx, AV_LOG_WARNING, "Can not process SOS before SOF, skipping\n");
01469                         break;
01470                     }
01471                     ff_mjpeg_decode_sos(s);
01472                     /* buggy avid puts EOI every 10-20th frame */
01473                     /* if restart period is over process EOI */
01474                     if ((s->buggy_avid && !s->interlaced) || s->restart_interval)
01475                         goto eoi_parser;
01476                     break;
01477                 case DRI:
01478                     mjpeg_decode_dri(s);
01479                     break;
01480                 case SOF5:
01481                 case SOF6:
01482                 case SOF7:
01483                 case SOF9:
01484                 case SOF10:
01485                 case SOF11:
01486                 case SOF13:
01487                 case SOF14:
01488                 case SOF15:
01489                 case JPG:
01490                     av_log(avctx, AV_LOG_ERROR, "mjpeg: unsupported coding type (%x)\n", start_code);
01491                     break;
01492 //                default:
01493 //                    printf("mjpeg: unsupported marker (%x)\n", start_code);
01494 //                    break;
01495                 }
01496 
01497 not_the_end:
01498                 /* eof process start code */
01499                 buf_ptr += (get_bits_count(&s->gb)+7)/8;
01500                 av_log(avctx, AV_LOG_DEBUG, "marker parser used %d bytes (%d bits)\n",
01501                        (get_bits_count(&s->gb)+7)/8, get_bits_count(&s->gb));
01502             }
01503         }
01504     }
01505     if (s->got_picture) {
01506         av_log(avctx, AV_LOG_WARNING, "EOI missing, emulating\n");
01507         goto eoi_parser;
01508     }
01509     av_log(avctx, AV_LOG_FATAL, "No JPEG data found in image\n");
01510     return -1;
01511 the_end:
01512     av_log(avctx, AV_LOG_DEBUG, "mjpeg decode frame unused %td bytes\n", buf_end - buf_ptr);
01513 //    return buf_end - buf_ptr;
01514     return buf_ptr - buf;
01515 }
01516 
01517 av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
01518 {
01519     MJpegDecodeContext *s = avctx->priv_data;
01520     int i, j;
01521 
01522     if (s->picture.data[0])
01523         avctx->release_buffer(avctx, &s->picture);
01524 
01525     av_free(s->buffer);
01526     av_free(s->qscale_table);
01527     av_freep(&s->ljpeg_buffer);
01528     s->ljpeg_buffer_size=0;
01529 
01530     for(i=0;i<2;i++) {
01531         for(j=0;j<4;j++)
01532             free_vlc(&s->vlcs[i][j]);
01533     }
01534     for(i=0; i<MAX_COMPONENTS; i++) {
01535         av_freep(&s->blocks[i]);
01536         av_freep(&s->last_nnz[i]);
01537     }
01538     return 0;
01539 }
01540 
01541 AVCodec mjpeg_decoder = {
01542     "mjpeg",
01543     AVMEDIA_TYPE_VIDEO,
01544     CODEC_ID_MJPEG,
01545     sizeof(MJpegDecodeContext),
01546     ff_mjpeg_decode_init,
01547     NULL,
01548     ff_mjpeg_decode_end,
01549     ff_mjpeg_decode_frame,
01550     CODEC_CAP_DR1,
01551     NULL,
01552     .long_name = NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),
01553 };
01554 
01555 AVCodec thp_decoder = {
01556     "thp",
01557     AVMEDIA_TYPE_VIDEO,
01558     CODEC_ID_THP,
01559     sizeof(MJpegDecodeContext),
01560     ff_mjpeg_decode_init,
01561     NULL,
01562     ff_mjpeg_decode_end,
01563     ff_mjpeg_decode_frame,
01564     CODEC_CAP_DR1,
01565     NULL,
01566     .long_name = NULL_IF_CONFIG_SMALL("Nintendo Gamecube THP video"),
01567 };