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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, const uint8_t *buf, int buf_size) {
00047     SUNRASTContext * const s = avctx->priv_data;
00048     AVFrame *picture = data;
00049     AVFrame * const p = &s->picture;
00050     unsigned int w, h, depth, type, maptype, maplength, stride, x, y, len, alen;
00051     uint8_t *ptr;
00052     const uint8_t *bufstart = buf;
00053 
00054     if (AV_RB32(buf) != 0x59a66a95) {
00055         av_log(avctx, AV_LOG_ERROR, "this is not sunras encoded data\n");
00056         return -1;
00057     }
00058 
00059     w         = AV_RB32(buf+4);
00060     h         = AV_RB32(buf+8);
00061     depth     = AV_RB32(buf+12);
00062     type      = AV_RB32(buf+20);
00063     maptype   = AV_RB32(buf+24);
00064     maplength = AV_RB32(buf+28);
00065 
00066     if (type > RT_BYTE_ENCODED && type <= RT_FORMAT_IFF) {
00067         av_log(avctx, AV_LOG_ERROR, "unsupported (compression) type\n");
00068         return -1;
00069     }
00070     if (type > RT_FORMAT_IFF) {
00071         av_log(avctx, AV_LOG_ERROR, "invalid (compression) type\n");
00072         return -1;
00073     }
00074     if (maptype & ~1) {
00075         av_log(avctx, AV_LOG_ERROR, "invalid colormap type\n");
00076         return -1;
00077     }
00078 
00079     buf += 32;
00080 
00081     switch (depth) {
00082         case 1:
00083             avctx->pix_fmt = PIX_FMT_MONOWHITE;
00084             break;
00085         case 8:
00086             avctx->pix_fmt = PIX_FMT_PAL8;
00087             break;
00088         case 24:
00089             avctx->pix_fmt = PIX_FMT_BGR24;
00090             break;
00091         default:
00092             av_log(avctx, AV_LOG_ERROR, "invalid depth\n");
00093             return -1;
00094     }
00095 
00096     if (p->data[0])
00097         avctx->release_buffer(avctx, p);
00098 
00099     if (avcodec_check_dimensions(avctx, w, h))
00100         return -1;
00101     if (w != avctx->width || h != avctx->height)
00102         avcodec_set_dimensions(avctx, w, h);
00103     if (avctx->get_buffer(avctx, p) < 0) {
00104         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00105         return -1;
00106     }
00107 
00108     p->pict_type = FF_I_TYPE;
00109 
00110     if (depth != 8 && maplength) {
00111         av_log(avctx, AV_LOG_WARNING, "useless colormap found or file is corrupted, trying to recover\n");
00112 
00113     } else if (depth == 8) {
00114         unsigned int len = maplength / 3;
00115 
00116         if (!maplength) {
00117             av_log(avctx, AV_LOG_ERROR, "colormap expected\n");
00118             return -1;
00119         }
00120         if (maplength % 3 || maplength > 768) {
00121             av_log(avctx, AV_LOG_WARNING, "invalid colormap length\n");
00122             return -1;
00123         }
00124 
00125         ptr = p->data[1];
00126         for (x=0; x<len; x++, ptr+=4)
00127             *(uint32_t *)ptr = (buf[x]<<16) + (buf[len+x]<<8) + buf[len+len+x];
00128     }
00129 
00130     buf += maplength;
00131 
00132     ptr    = p->data[0];
00133     stride = p->linesize[0];
00134 
00135     /* scanlines are aligned on 16 bit boundaries */
00136     len  = (depth * w + 7) >> 3;
00137     alen = len + (len&1);
00138 
00139     if (type == RT_BYTE_ENCODED) {
00140         int value, run;
00141         uint8_t *end = ptr + h*stride;
00142 
00143         x = 0;
00144         while (ptr != end) {
00145             run = 1;
00146             if ((value = *buf++) == 0x80) {
00147                 run = *buf++ + 1;
00148                 if (run != 1)
00149                     value = *buf++;
00150             }
00151             while (run--) {
00152                 if (x < len)
00153                     ptr[x] = value;
00154                 if (++x >= alen) {
00155                     x = 0;
00156                     ptr += stride;
00157                     if (ptr == end)
00158                         break;
00159                 }
00160             }
00161         }
00162     } else {
00163         for (y=0; y<h; y++) {
00164             memcpy(ptr, buf, len);
00165             ptr += stride;
00166             buf += alen;
00167         }
00168     }
00169 
00170     *picture = s->picture;
00171     *data_size = sizeof(AVFrame);
00172 
00173     return buf - bufstart;
00174 }
00175 
00176 static av_cold int sunrast_end(AVCodecContext *avctx) {
00177     SUNRASTContext *s = avctx->priv_data;
00178 
00179     if(s->picture.data[0])
00180         avctx->release_buffer(avctx, &s->picture);
00181 
00182     return 0;
00183 }
00184 
00185 AVCodec sunrast_decoder = {
00186     "sunrast",
00187     CODEC_TYPE_VIDEO,
00188     CODEC_ID_SUNRAST,
00189     sizeof(SUNRASTContext),
00190     sunrast_init,
00191     NULL,
00192     sunrast_end,
00193     sunrast_decode_frame,
00194     0,
00195     NULL,
00196     .long_name = NULL_IF_CONFIG_SMALL("Sun Rasterfile image"),
00197 };

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