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libavcodec/sunrast.c

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00001 /*
00002  * Sun Rasterfile (.sun/.ras/im{1,8,24}/.sunras) image decoder
00003  * Copyright (c) 2007, 2008 Ivo van Poorten
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/intreadwrite.h"
00023 #include "avcodec.h"
00024 
00025 #define RT_OLD          0
00026 #define RT_STANDARD     1
00027 #define RT_BYTE_ENCODED 2
00028 #define RT_FORMAT_RGB   3
00029 #define RT_FORMAT_TIFF  4
00030 #define RT_FORMAT_IFF   5
00031 
00032 typedef struct SUNRASTContext {
00033     AVFrame picture;
00034 } SUNRASTContext;
00035 
00036 static av_cold int sunrast_init(AVCodecContext *avctx) {
00037     SUNRASTContext *s = avctx->priv_data;
00038 
00039     avcodec_get_frame_defaults(&s->picture);
00040     avctx->coded_frame= &s->picture;
00041 
00042     return 0;
00043 }
00044 
00045 static int sunrast_decode_frame(AVCodecContext *avctx, void *data,
00046                                 int *data_size, AVPacket *avpkt) {
00047     const uint8_t *buf = avpkt->data;
00048     SUNRASTContext * const s = avctx->priv_data;
00049     AVFrame *picture = data;
00050     AVFrame * const p = &s->picture;
00051     unsigned int w, h, depth, type, maptype, maplength, stride, x, y, len, alen;
00052     uint8_t *ptr;
00053     const uint8_t *bufstart = buf;
00054 
00055     if (AV_RB32(buf) != 0x59a66a95) {
00056         av_log(avctx, AV_LOG_ERROR, "this is not sunras encoded data\n");
00057         return -1;
00058     }
00059 
00060     w         = AV_RB32(buf+4);
00061     h         = AV_RB32(buf+8);
00062     depth     = AV_RB32(buf+12);
00063     type      = AV_RB32(buf+20);
00064     maptype   = AV_RB32(buf+24);
00065     maplength = AV_RB32(buf+28);
00066 
00067     if (type == RT_FORMAT_TIFF || type == RT_FORMAT_IFF) {
00068         av_log(avctx, AV_LOG_ERROR, "unsupported (compression) type\n");
00069         return -1;
00070     }
00071     if (type > RT_FORMAT_IFF) {
00072         av_log(avctx, AV_LOG_ERROR, "invalid (compression) type\n");
00073         return -1;
00074     }
00075     if (maptype & ~1) {
00076         av_log(avctx, AV_LOG_ERROR, "invalid colormap type\n");
00077         return -1;
00078     }
00079 
00080     buf += 32;
00081 
00082     switch (depth) {
00083         case 1:
00084             avctx->pix_fmt = PIX_FMT_MONOWHITE;
00085             break;
00086         case 8:
00087             avctx->pix_fmt = PIX_FMT_PAL8;
00088             break;
00089         case 24:
00090             avctx->pix_fmt = (type == RT_FORMAT_RGB) ? PIX_FMT_RGB24 : PIX_FMT_BGR24;
00091             break;
00092         default:
00093             av_log(avctx, AV_LOG_ERROR, "invalid depth\n");
00094             return -1;
00095     }
00096 
00097     if (p->data[0])
00098         avctx->release_buffer(avctx, p);
00099 
00100     if (avcodec_check_dimensions(avctx, w, h))
00101         return -1;
00102     if (w != avctx->width || h != avctx->height)
00103         avcodec_set_dimensions(avctx, w, h);
00104     if (avctx->get_buffer(avctx, p) < 0) {
00105         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00106         return -1;
00107     }
00108 
00109     p->pict_type = FF_I_TYPE;
00110 
00111     if (depth != 8 && maplength) {
00112         av_log(avctx, AV_LOG_WARNING, "useless colormap found or file is corrupted, trying to recover\n");
00113 
00114     } else if (depth == 8) {
00115         unsigned int len = maplength / 3;
00116 
00117         if (!maplength) {
00118             av_log(avctx, AV_LOG_ERROR, "colormap expected\n");
00119             return -1;
00120         }
00121         if (maplength % 3 || maplength > 768) {
00122             av_log(avctx, AV_LOG_WARNING, "invalid colormap length\n");
00123             return -1;
00124         }
00125 
00126         ptr = p->data[1];
00127         for (x=0; x<len; x++, ptr+=4)
00128             *(uint32_t *)ptr = (buf[x]<<16) + (buf[len+x]<<8) + buf[len+len+x];
00129     }
00130 
00131     buf += maplength;
00132 
00133     ptr    = p->data[0];
00134     stride = p->linesize[0];
00135 
00136     /* scanlines are aligned on 16 bit boundaries */
00137     len  = (depth * w + 7) >> 3;
00138     alen = len + (len&1);
00139 
00140     if (type == RT_BYTE_ENCODED) {
00141         int value, run;
00142         uint8_t *end = ptr + h*stride;
00143 
00144         x = 0;
00145         while (ptr != end) {
00146             run = 1;
00147             if ((value = *buf++) == 0x80) {
00148                 run = *buf++ + 1;
00149                 if (run != 1)
00150                     value = *buf++;
00151             }
00152             while (run--) {
00153                 if (x < len)
00154                     ptr[x] = value;
00155                 if (++x >= alen) {
00156                     x = 0;
00157                     ptr += stride;
00158                     if (ptr == end)
00159                         break;
00160                 }
00161             }
00162         }
00163     } else {
00164         for (y=0; y<h; y++) {
00165             memcpy(ptr, buf, len);
00166             ptr += stride;
00167             buf += alen;
00168         }
00169     }
00170 
00171     *picture = s->picture;
00172     *data_size = sizeof(AVFrame);
00173 
00174     return buf - bufstart;
00175 }
00176 
00177 static av_cold int sunrast_end(AVCodecContext *avctx) {
00178     SUNRASTContext *s = avctx->priv_data;
00179 
00180     if(s->picture.data[0])
00181         avctx->release_buffer(avctx, &s->picture);
00182 
00183     return 0;
00184 }
00185 
00186 AVCodec sunrast_decoder = {
00187     "sunrast",
00188     AVMEDIA_TYPE_VIDEO,
00189     CODEC_ID_SUNRAST,
00190     sizeof(SUNRASTContext),
00191     sunrast_init,
00192     NULL,
00193     sunrast_end,
00194     sunrast_decode_frame,
00195     CODEC_CAP_DR1,
00196     NULL,
00197     .long_name = NULL_IF_CONFIG_SMALL("Sun Rasterfile image"),
00198 };

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