/*
  * FLV decoding.

  *

  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 

 #include "libavutil/imgutils.h"

 #include "flv.h"
 #include "h263.h"
 #include "mpegvideo.h"

 #include "mpegvideodata.h"

 int ff_flv_decode_picture_header(MpegEncContext *s)
 {
     int format, width, height;
 
     /* picture header */
     if (get_bits_long(&s->gb, 17) != 1) {
         av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");

         return AVERROR_INVALIDDATA;

     }
     format = get_bits(&s->gb, 5);
     if (format != 0 && format != 1) {
         av_log(s->avctx, AV_LOG_ERROR, "Bad picture format\n");

         return AVERROR_INVALIDDATA;

     }

     s->h263_flv       = format + 1;

     s->picture_number = get_bits(&s->gb, 8); /* picture timestamp */

     format            = get_bits(&s->gb, 3);

     switch (format) {
     case 0:

         width  = get_bits(&s->gb, 8);

         height = get_bits(&s->gb, 8);
         break;
     case 1:

         width  = get_bits(&s->gb, 16);

         height = get_bits(&s->gb, 16);
         break;
     case 2:

         width  = 352;

         height = 288;
         break;
     case 3:

         width  = 176;

         height = 144;
         break;
     case 4:

         width  = 128;

         height = 96;
         break;
     case 5:

         width  = 320;

         height = 240;
         break;
     case 6:

         width  = 160;

         height = 120;
         break;
     default:
         width = height = 0;
         break;
     }

     if (av_image_check_size(width, height, 0, s->avctx))

         return AVERROR(EINVAL);

     s->width  = width;

     s->height = height;
 

     s->pict_type = AV_PICTURE_TYPE_I + get_bits(&s->gb, 2);

     s->droppable = s->pict_type > AV_PICTURE_TYPE_P;
     if (s->droppable)

         s->pict_type = AV_PICTURE_TYPE_P;

 
     skip_bits1(&s->gb); /* deblocking flag */

     s->chroma_qscale = s->qscale = get_bits(&s->gb, 5);

 
     s->h263_plus = 0;
 

     s->unrestricted_mv   = 1;

     s->h263_long_vectors = 0;
 
     /* PEI */

     if (skip_1stop_8data_bits(&s->gb) < 0)
         return AVERROR_INVALIDDATA;

     s->f_code = 1;
 

     if (s->ehc_mode)
         s->avctx->sample_aspect_ratio= (AVRational){1,2};
 

     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {

         av_log(s->avctx, AV_LOG_DEBUG, "%c esc_type:%d, qp:%d num:%d\n",

                s->droppable ? 'D' : av_get_picture_type_char(s->pict_type),
                s->h263_flv - 1, s->qscale, s->picture_number);

     }
 

     s->y_dc_scale_table = s->c_dc_scale_table = ff_mpeg1_dc_scale_table;

 
     return 0;
 }
 

 AVCodec ff_flv_decoder = {

     .name           = "flv",

     .long_name      = NULL_IF_CONFIG_SMALL("FLV / Sorenson Spark / Sorenson H.263 (Flash Video)"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_FLV1,

     .priv_data_size = sizeof(MpegEncContext),
     .init           = ff_h263_decode_init,
     .close          = ff_h263_decode_end,
     .decode         = ff_h263_decode_frame,

     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,

     .caps_internal  = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,

     .max_lowres     = 3,

     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
                                                      AV_PIX_FMT_NONE },

 };