/*
  * 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 "mpegvideo.h"

 #include "h263.h"

 #include "flv.h"

 #include "libavutil/imgutils.h"

 
 void ff_flv2_decode_ac_esc(GetBitContext *gb, int *level, int *run, int *last){
     int is11 = get_bits1(gb);
     *last = get_bits1(gb);
     *run = get_bits(gb, 6);
     if(is11){
         *level = get_sbits(gb, 11);
     } else {
         *level = get_sbits(gb, 7);
     }
 }
 
 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 -1;
     }
     format = get_bits(&s->gb, 5);
     if (format != 0 && format != 1) {
         av_log(s->avctx, AV_LOG_ERROR, "Bad picture format\n");
         return -1;
     }
     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 -1;
     s->width = width;
     s->height = height;
 

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

     if (s->dropable)

         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 */
     while (get_bits1(&s->gb) != 0) {
         skip_bits(&s->gb, 8);
     }
     s->f_code = 1;
 
     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->dropable ? '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",
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = CODEC_ID_FLV1,
     .priv_data_size = sizeof(MpegEncContext),
     .init           = ff_h263_decode_init,
     .close          = ff_h263_decode_end,
     .decode         = ff_h263_decode_frame,
     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,

     .max_lowres= 3,

     .long_name= NULL_IF_CONFIG_SMALL("Flash Video (FLV) / Sorenson Spark / Sorenson H.263"),
     .pix_fmts= ff_pixfmt_list_420,
 };