yading@10: /*
yading@10:  * H.263i decoder
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include "mpegvideo.h"
yading@10: #include "h263.h"
yading@10: 
yading@10: /* don't understand why they choose a different header ! */
yading@10: int ff_intel_h263_decode_picture_header(MpegEncContext *s)
yading@10: {
yading@10:     int format;
yading@10: 
yading@10:     /* picture header */
yading@10:     if (get_bits_long(&s->gb, 22) != 0x20) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
yading@10:         return -1;
yading@10:     }
yading@10:     s->picture_number = get_bits(&s->gb, 8); /* picture timestamp */
yading@10: 
yading@10:     if (get_bits1(&s->gb) != 1) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "Bad marker\n");
yading@10:         return -1;      /* marker */
yading@10:     }
yading@10:     if (get_bits1(&s->gb) != 0) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "Bad H263 id\n");
yading@10:         return -1;      /* h263 id */
yading@10:     }
yading@10:     skip_bits1(&s->gb);         /* split screen off */
yading@10:     skip_bits1(&s->gb);         /* camera  off */
yading@10:     skip_bits1(&s->gb);         /* freeze picture release off */
yading@10: 
yading@10:     format = get_bits(&s->gb, 3);
yading@10:     if (format == 0 || format == 6) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "Intel H263 free format not supported\n");
yading@10:         return -1;
yading@10:     }
yading@10:     s->h263_plus = 0;
yading@10: 
yading@10:     s->pict_type = AV_PICTURE_TYPE_I + get_bits1(&s->gb);
yading@10: 
yading@10:     s->h263_long_vectors = get_bits1(&s->gb);
yading@10: 
yading@10:     if (get_bits1(&s->gb) != 0) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "SAC not supported\n");
yading@10:         return -1;      /* SAC: off */
yading@10:     }
yading@10:     s->obmc= get_bits1(&s->gb);
yading@10:     s->unrestricted_mv = s->obmc || s->h263_long_vectors;
yading@10:     s->pb_frame = get_bits1(&s->gb);
yading@10: 
yading@10:     if (format < 6) {
yading@10:         s->width = ff_h263_format[format][0];
yading@10:         s->height = ff_h263_format[format][1];
yading@10:         s->avctx->sample_aspect_ratio.num = 12;
yading@10:         s->avctx->sample_aspect_ratio.den = 11;
yading@10:     } else {
yading@10:         format = get_bits(&s->gb, 3);
yading@10:         if(format == 0 || format == 7){
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Wrong Intel H263 format\n");
yading@10:             return -1;
yading@10:         }
yading@10:         if(get_bits(&s->gb, 2))
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n");
yading@10:         s->loop_filter = get_bits1(&s->gb) * !s->avctx->lowres;
yading@10:         if(get_bits1(&s->gb))
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n");
yading@10:         if(get_bits1(&s->gb))
yading@10:             s->pb_frame = 2;
yading@10:         if(get_bits(&s->gb, 5))
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n");
yading@10:         if(get_bits(&s->gb, 5) != 1)
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Invalid marker\n");
yading@10:     }
yading@10:     if(format == 6){
yading@10:         int ar = get_bits(&s->gb, 4);
yading@10:         skip_bits(&s->gb, 9); // display width
yading@10:         skip_bits1(&s->gb);
yading@10:         skip_bits(&s->gb, 9); // display height
yading@10:         if(ar == 15){
yading@10:             s->avctx->sample_aspect_ratio.num = get_bits(&s->gb, 8); // aspect ratio - width
yading@10:             s->avctx->sample_aspect_ratio.den = get_bits(&s->gb, 8); // aspect ratio - height
yading@10:         } else {
yading@10:             s->avctx->sample_aspect_ratio = ff_h263_pixel_aspect[ar];
yading@10:         }
yading@10:         if (s->avctx->sample_aspect_ratio.num == 0)
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Invalid aspect ratio.\n");
yading@10:     }
yading@10: 
yading@10:     s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
yading@10:     skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */
yading@10: 
yading@10:     if(s->pb_frame){
yading@10:         skip_bits(&s->gb, 3); //temporal reference for B-frame
yading@10:         skip_bits(&s->gb, 2); //dbquant
yading@10:     }
yading@10: 
yading@10:     /* PEI */
yading@10:     while (get_bits1(&s->gb) != 0) {
yading@10:         skip_bits(&s->gb, 8);
yading@10:     }
yading@10:     s->f_code = 1;
yading@10: 
yading@10:     s->y_dc_scale_table=
yading@10:     s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
yading@10: 
yading@10:     ff_h263_show_pict_info(s);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_h263i_decoder = {
yading@10:     .name           = "h263i",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_H263I,
yading@10:     .priv_data_size = sizeof(MpegEncContext),
yading@10:     .init           = ff_h263_decode_init,
yading@10:     .close          = ff_h263_decode_end,
yading@10:     .decode         = ff_h263_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Intel H.263"),
yading@10:     .pix_fmts       = ff_pixfmt_list_420,
yading@10: };