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libavcodec/rawdec.c

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00001 /*
00002  * Raw Video Decoder
00003  * Copyright (c) 2001 Fabrice Bellard
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 
00027 #include "avcodec.h"
00028 #include "raw.h"
00029 #include "libavutil/intreadwrite.h"
00030 
00031 typedef struct RawVideoContext {
00032     unsigned char * buffer;  /* block of memory for holding one frame */
00033     int             length;  /* number of bytes in buffer */
00034     int flip;
00035     AVFrame pic;             
00036 } RawVideoContext;
00037 
00038 static const PixelFormatTag pixelFormatBpsAVI[] = {
00039     { PIX_FMT_PAL8,    4 },
00040     { PIX_FMT_PAL8,    8 },
00041     { PIX_FMT_RGB555, 15 },
00042     { PIX_FMT_RGB555, 16 },
00043     { PIX_FMT_BGR24,  24 },
00044     { PIX_FMT_RGB32,  32 },
00045     { PIX_FMT_NONE, 0 },
00046 };
00047 
00048 static const PixelFormatTag pixelFormatBpsMOV[] = {
00049     { PIX_FMT_MONOWHITE, 1 },
00050     { PIX_FMT_PAL8,      2 },
00051     { PIX_FMT_PAL8,      4 },
00052     { PIX_FMT_PAL8,      8 },
00053     // FIXME swscale does not support 16 bit in .mov, sample 16bit.mov
00054     // http://developer.apple.com/documentation/QuickTime/QTFF/QTFFChap3/qtff3.html
00055     { PIX_FMT_RGB555BE, 16 },
00056     { PIX_FMT_RGB24,    24 },
00057     { PIX_FMT_ARGB,     32 },
00058     { PIX_FMT_NONE, 0 },
00059 };
00060 
00061 static enum PixelFormat findPixelFormat(const PixelFormatTag *tags, unsigned int fourcc)
00062 {
00063     while (tags->pix_fmt >= 0) {
00064         if (tags->fourcc == fourcc)
00065             return tags->pix_fmt;
00066         tags++;
00067     }
00068     return PIX_FMT_YUV420P;
00069 }
00070 
00071 static av_cold int raw_init_decoder(AVCodecContext *avctx)
00072 {
00073     RawVideoContext *context = avctx->priv_data;
00074 
00075     if (avctx->codec_tag == MKTAG('r','a','w',' '))
00076         avctx->pix_fmt = findPixelFormat(pixelFormatBpsMOV, avctx->bits_per_coded_sample);
00077     else if (avctx->codec_tag)
00078         avctx->pix_fmt = findPixelFormat(ff_raw_pixelFormatTags, avctx->codec_tag);
00079     else if (avctx->bits_per_coded_sample)
00080         avctx->pix_fmt = findPixelFormat(pixelFormatBpsAVI, avctx->bits_per_coded_sample);
00081 
00082     context->length = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
00083     context->buffer = av_malloc(context->length);
00084     context->pic.pict_type = FF_I_TYPE;
00085     context->pic.key_frame = 1;
00086 
00087     avctx->coded_frame= &context->pic;
00088 
00089     if (!context->buffer)
00090         return -1;
00091 
00092     if((avctx->extradata_size >= 9 && !memcmp(avctx->extradata + avctx->extradata_size - 9, "BottomUp", 9)) ||
00093        avctx->codec_tag == MKTAG( 3 ,  0 ,  0 ,  0 ))
00094         context->flip=1;
00095 
00096     return 0;
00097 }
00098 
00099 static void flip(AVCodecContext *avctx, AVPicture * picture){
00100     picture->data[0] += picture->linesize[0] * (avctx->height-1);
00101     picture->linesize[0] *= -1;
00102 }
00103 
00104 static int raw_decode(AVCodecContext *avctx,
00105                             void *data, int *data_size,
00106                             AVPacket *avpkt)
00107 {
00108     const uint8_t *buf = avpkt->data;
00109     int buf_size = avpkt->size;
00110     RawVideoContext *context = avctx->priv_data;
00111 
00112     AVFrame * frame = (AVFrame *) data;
00113     AVPicture * picture = (AVPicture *) data;
00114 
00115     frame->interlaced_frame = avctx->coded_frame->interlaced_frame;
00116     frame->top_field_first = avctx->coded_frame->top_field_first;
00117 
00118     //2bpp and 4bpp raw in avi and mov (yes this is ugly ...)
00119     if((avctx->bits_per_coded_sample == 4 || avctx->bits_per_coded_sample == 2) &&
00120        avctx->pix_fmt==PIX_FMT_PAL8 &&
00121        (!avctx->codec_tag || avctx->codec_tag == MKTAG('r','a','w',' '))){
00122         int i;
00123         uint8_t *dst = context->buffer + 256*4;
00124         buf_size = context->length - 256*4;
00125         if (avctx->bits_per_coded_sample == 4){
00126             for(i=0; 2*i+1 < buf_size; i++){
00127                 dst[2*i+0]= buf[i]>>4;
00128                 dst[2*i+1]= buf[i]&15;
00129             }
00130         } else
00131             for(i=0; 4*i+3 < buf_size; i++){
00132                 dst[4*i+0]= buf[i]>>6;
00133                 dst[4*i+1]= buf[i]>>4&3;
00134                 dst[4*i+2]= buf[i]>>2&3;
00135                 dst[4*i+3]= buf[i]   &3;
00136             }
00137         buf= dst;
00138     }
00139 
00140     if(avctx->codec_tag == MKTAG('A', 'V', '1', 'x') ||
00141        avctx->codec_tag == MKTAG('A', 'V', 'u', 'p'))
00142         buf += buf_size - context->length;
00143 
00144     if(buf_size < context->length - (avctx->pix_fmt==PIX_FMT_PAL8 ? 256*4 : 0))
00145         return -1;
00146 
00147     avpicture_fill(picture, buf, avctx->pix_fmt, avctx->width, avctx->height);
00148     if(avctx->pix_fmt==PIX_FMT_PAL8 && buf_size < context->length){
00149         frame->data[1]= context->buffer;
00150     }
00151     if (avctx->palctrl && avctx->palctrl->palette_changed) {
00152         memcpy(frame->data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
00153         avctx->palctrl->palette_changed = 0;
00154     }
00155     if(avctx->pix_fmt==PIX_FMT_BGR24 && ((frame->linesize[0]+3)&~3)*avctx->height <= buf_size)
00156         frame->linesize[0] = (frame->linesize[0]+3)&~3;
00157 
00158     if(context->flip)
00159         flip(avctx, picture);
00160 
00161     if (   avctx->codec_tag == MKTAG('Y', 'V', '1', '2')
00162         || avctx->codec_tag == MKTAG('Y', 'V', 'U', '9'))
00163         FFSWAP(uint8_t *, picture->data[1], picture->data[2]);
00164 
00165     if(avctx->codec_tag == AV_RL32("yuv2") &&
00166        avctx->pix_fmt   == PIX_FMT_YUYV422) {
00167         int x, y;
00168         uint8_t *line = picture->data[0];
00169         for(y = 0; y < avctx->height; y++) {
00170             for(x = 0; x < avctx->width; x++)
00171                 line[2*x + 1] ^= 0x80;
00172             line += picture->linesize[0];
00173         }
00174     }
00175 
00176     *data_size = sizeof(AVPicture);
00177     return buf_size;
00178 }
00179 
00180 static av_cold int raw_close_decoder(AVCodecContext *avctx)
00181 {
00182     RawVideoContext *context = avctx->priv_data;
00183 
00184     av_freep(&context->buffer);
00185     return 0;
00186 }
00187 
00188 AVCodec rawvideo_decoder = {
00189     "rawvideo",
00190     AVMEDIA_TYPE_VIDEO,
00191     CODEC_ID_RAWVIDEO,
00192     sizeof(RawVideoContext),
00193     raw_init_decoder,
00194     NULL,
00195     raw_close_decoder,
00196     raw_decode,
00197     .long_name = NULL_IF_CONFIG_SMALL("raw video"),
00198 };

Generated on Fri Sep 16 2011 17:17:42 for FFmpeg by  doxygen 1.7.1