libavcodec/rawdec.c

   1 /*
   2  * Raw Video Decoder
   3  * Copyright (c) 2001 Fabrice Bellard.
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file rawdec.c
  24  * Raw Video Decoder
  25  */
  26
  27 #include "avcodec.h"
  28 #include "raw.h"
  29
  30 typedef struct RawVideoContext {
  31     unsigned char * buffer;  /* block of memory for holding one frame */
  32     int             length;  /* number of bytes in buffer */
  33     AVFrame pic;             ///< AVCodecContext.coded_frame
  34 } RawVideoContext;
  35
  36 static const PixelFormatTag pixelFormatBpsAVI[] = {
  37     { PIX_FMT_PAL8,    4 },
  38     { PIX_FMT_PAL8,    8 },
  39     { PIX_FMT_RGB555, 15 },
  40     { PIX_FMT_RGB555, 16 },
  41     { PIX_FMT_BGR24,  24 },
  42     { PIX_FMT_RGB32,  32 },
  43     { PIX_FMT_NONE, 0 },
  44 };
  45
  46 static const PixelFormatTag pixelFormatBpsMOV[] = {
  47     /* FIXME fix swscaler to support those */
  48     /* http://developer.apple.com/documentation/QuickTime/QTFF/QTFFChap3/chapter_4_section_2.html */
  49     { PIX_FMT_PAL8,      4 },
  50     { PIX_FMT_PAL8,      8 },
  51     { PIX_FMT_BGR555,   16 },
  52     { PIX_FMT_RGB24,    24 },
  53     { PIX_FMT_BGR32_1,  32 },
  54     { PIX_FMT_NONE, 0 },
  55 };
  56
  57 static enum PixelFormat findPixelFormat(const PixelFormatTag *tags, unsigned int fourcc)
  58 {
  59     while (tags->pix_fmt >= 0) {
  60         if (tags->fourcc == fourcc)
  61             return tags->pix_fmt;
  62         tags++;
  63     }
  64     return PIX_FMT_YUV420P;
  65 }
  66
  67 static av_cold int raw_init_decoder(AVCodecContext *avctx)
  68 {
  69     RawVideoContext *context = avctx->priv_data;
  70
  71     if (avctx->codec_tag == MKTAG('r','a','w',' '))
  72         avctx->pix_fmt = findPixelFormat(pixelFormatBpsMOV, avctx->bits_per_coded_sample);
  73     else if (avctx->codec_tag)
  74         avctx->pix_fmt = findPixelFormat(ff_raw_pixelFormatTags, avctx->codec_tag);
  75     else if (avctx->bits_per_coded_sample)
  76         avctx->pix_fmt = findPixelFormat(pixelFormatBpsAVI, avctx->bits_per_coded_sample);
  77
  78     context->length = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
  79     context->buffer = av_malloc(context->length);
  80     context->pic.pict_type = FF_I_TYPE;
  81     context->pic.key_frame = 1;
  82
  83     avctx->coded_frame= &context->pic;
  84
  85     if (!context->buffer)
  86         return -1;
  87
  88     return 0;
  89 }
  90
  91 static void flip(AVCodecContext *avctx, AVPicture * picture){
  92     if(!avctx->codec_tag && avctx->bits_per_coded_sample && picture->linesize[2]==0){
  93         picture->data[0] += picture->linesize[0] * (avctx->height-1);
  94         picture->linesize[0] *= -1;
  95     }
  96 }
  97
  98 static int raw_decode(AVCodecContext *avctx,
  99                             void *data, int *data_size,
 100                             const uint8_t *buf, int buf_size)
 101 {
 102     RawVideoContext *context = avctx->priv_data;
 103
 104     AVFrame * frame = (AVFrame *) data;
 105     AVPicture * picture = (AVPicture *) data;
 106
 107     frame->interlaced_frame = avctx->coded_frame->interlaced_frame;
 108     frame->top_field_first = avctx->coded_frame->top_field_first;
 109
 110     //4bpp raw in avi and mov (yes this is ugly ...)
 111     if(avctx->bits_per_coded_sample == 4 && avctx->pix_fmt==PIX_FMT_PAL8 &&
 112        (!avctx->codec_tag || avctx->codec_tag == MKTAG('r','a','w',' '))){
 113         int i;
 114         for(i=256*2; i+1 < context->length>>1; i++){
 115             context->buffer[2*i+0]= buf[i-256*2]>>4;
 116             context->buffer[2*i+1]= buf[i-256*2]&15;
 117         }
 118         buf= context->buffer + 256*4;
 119         buf_size= context->length - 256*4;
 120     }
 121
 122     if(buf_size < context->length - (avctx->pix_fmt==PIX_FMT_PAL8 ? 256*4 : 0))
 123         return -1;
 124
 125     avpicture_fill(picture, buf, avctx->pix_fmt, avctx->width, avctx->height);
 126     if(avctx->pix_fmt==PIX_FMT_PAL8 && buf_size < context->length){
 127         frame->data[1]= context->buffer;
 128     }
 129     if (avctx->palctrl && avctx->palctrl->palette_changed) {
 130         memcpy(frame->data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
 131         avctx->palctrl->palette_changed = 0;
 132     }
 133
 134     flip(avctx, picture);
 135
 136     if (avctx->codec_tag == MKTAG('Y', 'V', '1', '2'))
 137     {
 138         // swap fields
 139         unsigned char *tmp = picture->data[1];
 140         picture->data[1] = picture->data[2];
 141         picture->data[2] = tmp;
 142     }
 143
 144     *data_size = sizeof(AVPicture);
 145     return buf_size;
 146 }
 147
 148 static av_cold int raw_close_decoder(AVCodecContext *avctx)
 149 {
 150     RawVideoContext *context = avctx->priv_data;
 151
 152     av_freep(&context->buffer);
 153     return 0;
 154 }
 155
 156 AVCodec rawvideo_decoder = {
 157     "rawvideo",
 158     CODEC_TYPE_VIDEO,
 159     CODEC_ID_RAWVIDEO,
 160     sizeof(RawVideoContext),
 161     raw_init_decoder,
 162     NULL,
 163     raw_close_decoder,
 164     raw_decode,
 165     .long_name = NULL_IF_CONFIG_SMALL("raw video"),
 166 };