quicktime/ffmpeg/libavcodec/raw.c

   1 /*
   2  * Raw Video Codec
   3  * Copyright (c) 2001 Fabrice Bellard.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 /**
  21  * @file raw.c
  22  * Raw Video Codec
  23  */
  24
  25 #include "avcodec.h"
  26
  27 typedef struct RawVideoContext {
  28     unsigned char * buffer;  /* block of memory for holding one frame */
  29     unsigned char * p;       /* current position in buffer */
  30     int             length;  /* number of bytes in buffer */
  31     AVFrame pic;             ///< AVCodecContext.coded_frame
  32 } RawVideoContext;
  33
  34 typedef struct PixleFormatTag {
  35     int pix_fmt;
  36     unsigned int fourcc;
  37 } PixelFormatTag;
  38
  39 const PixelFormatTag pixelFormatTags[] = {
  40     { PIX_FMT_YUV420P, MKTAG('I', '4', '2', '0') }, /* Planar formats */
  41     { PIX_FMT_YUV420P, MKTAG('I', 'Y', 'U', 'V') },
  42     { PIX_FMT_YUV410P, MKTAG('Y', 'U', 'V', '9') },
  43     { PIX_FMT_YUV411P, MKTAG('Y', '4', '1', 'B') },
  44     { PIX_FMT_YUV422P, MKTAG('Y', '4', '2', 'B') },
  45     { PIX_FMT_GRAY8,   MKTAG('Y', '8', '0', '0') },
  46     { PIX_FMT_GRAY8,   MKTAG(' ', ' ', 'Y', '8') },
  47
  48
  49     { PIX_FMT_YUV422,  MKTAG('Y', '4', '2', '2') }, /* Packed formats */
  50     { PIX_FMT_UYVY422, MKTAG('U', 'Y', 'V', 'Y') },
  51     { PIX_FMT_GRAY8,   MKTAG('G', 'R', 'E', 'Y') },
  52
  53     { -1, 0 },
  54 };
  55
  56 static int findPixelFormat(unsigned int fourcc)
  57 {
  58     const PixelFormatTag * tags = pixelFormatTags;
  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 unsigned int avcodec_pix_fmt_to_codec_tag(enum PixelFormat fmt)
  68 {
  69     const PixelFormatTag * tags = pixelFormatTags;
  70     while (tags->pix_fmt >= 0) {
  71         if (tags->pix_fmt == fmt)
  72             return tags->fourcc;
  73         tags++;
  74     }
  75     return 0;
  76 }
  77
  78 /* RAW Decoder Implementation */
  79
  80 static int raw_init_decoder(AVCodecContext *avctx)
  81 {
  82     RawVideoContext *context = avctx->priv_data;
  83
  84     if (avctx->codec_tag)
  85         avctx->pix_fmt = findPixelFormat(avctx->codec_tag);
  86     else if (avctx->bits_per_sample){
  87         switch(avctx->bits_per_sample){
  88         case 15: avctx->pix_fmt= PIX_FMT_RGB555; break;
  89         case 16: avctx->pix_fmt= PIX_FMT_RGB565; break;
  90         case 24: avctx->pix_fmt= PIX_FMT_BGR24 ; break;
  91         case 32: avctx->pix_fmt= PIX_FMT_RGBA32; break;
  92         }
  93     }
  94
  95     context->length = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
  96     context->buffer = av_malloc(context->length);
  97     context->p      = context->buffer;
  98     context->pic.pict_type = FF_I_TYPE;
  99     context->pic.key_frame = 1;
 100
 101     avctx->coded_frame= &context->pic;
 102
 103     if (!context->buffer)
 104         return -1;
 105
 106     return 0;
 107 }
 108
 109 static void flip(AVCodecContext *avctx, AVPicture * picture){
 110     if(!avctx->codec_tag && avctx->bits_per_sample && picture->linesize[1]==0){
 111         picture->data[0] += picture->linesize[0] * (avctx->height-1);
 112         picture->linesize[0] *= -1;
 113     }
 114 }
 115
 116 static int raw_decode(AVCodecContext *avctx,
 117                             void *data, int *data_size,
 118                             uint8_t *buf, int buf_size)
 119 {
 120     RawVideoContext *context = avctx->priv_data;
 121     int bytesNeeded;
 122
 123     AVPicture * picture = (AVPicture *) data;
 124
 125     /* Early out without copy if packet size == frame size */
 126     if (buf_size == context->length  &&  context->p == context->buffer) {
 127         avpicture_fill(picture, buf, avctx->pix_fmt, avctx->width, avctx->height);
 128         flip(avctx, picture);
 129         *data_size = sizeof(AVPicture);
 130         return buf_size;
 131     }
 132
 133     bytesNeeded = context->length - (context->p - context->buffer);
 134     if (buf_size < bytesNeeded) {
 135         memcpy(context->p, buf, buf_size);
 136         context->p += buf_size;
 137         return buf_size;
 138     }
 139
 140     memcpy(context->p, buf, bytesNeeded);
 141     context->p = context->buffer;
 142     avpicture_fill(picture, context->buffer, avctx->pix_fmt, avctx->width, avctx->height);
 143     flip(avctx, picture);
 144     *data_size = sizeof(AVPicture);
 145     return bytesNeeded;
 146 }
 147
 148 static 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 /* RAW Encoder Implementation */
 157
 158 static int raw_init_encoder(AVCodecContext *avctx)
 159 {
 160     avctx->coded_frame = (AVFrame *)avctx->priv_data;
 161     avctx->coded_frame->pict_type = FF_I_TYPE;
 162     avctx->coded_frame->key_frame = 1;
 163     if(!avctx->codec_tag)
 164         avctx->codec_tag = avcodec_pix_fmt_to_codec_tag(avctx->pix_fmt);
 165     return 0;
 166 }
 167
 168 static int raw_encode(AVCodecContext *avctx,
 169                             unsigned char *frame, int buf_size, void *data)
 170 {
 171     return avpicture_layout((AVPicture *)data, avctx->pix_fmt, avctx->width,
 172                                                avctx->height, frame, buf_size);
 173 }
 174
 175 #ifdef CONFIG_RAWVIDEO_ENCODER
 176 AVCodec rawvideo_encoder = {
 177     "rawvideo",
 178     CODEC_TYPE_VIDEO,
 179     CODEC_ID_RAWVIDEO,
 180     sizeof(AVFrame),
 181     raw_init_encoder,
 182     raw_encode,
 183 };
 184 #endif // CONFIG_RAWVIDEO_ENCODER
 185
 186 AVCodec rawvideo_decoder = {
 187     "rawvideo",
 188     CODEC_TYPE_VIDEO,
 189     CODEC_ID_RAWVIDEO,
 190     sizeof(RawVideoContext),
 191     raw_init_decoder,
 192     NULL,
 193     raw_close_decoder,
 194     raw_decode,
 195 };