| 1 | /* |
| 2 | * H.263i decoder |
| 3 | * |
| 4 | * This file is part of FFmpeg. |
| 5 | * |
| 6 | * FFmpeg is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * FFmpeg is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with FFmpeg; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 19 | */ |
| 20 | |
| 21 | #include "mpegvideo.h" |
| 22 | #include "h263.h" |
| 23 | |
| 24 | /* don't understand why they choose a different header ! */ |
| 25 | int ff_intel_h263_decode_picture_header(MpegEncContext *s) |
| 26 | { |
| 27 | int format; |
| 28 | |
| 29 | if (get_bits_left(&s->gb) == 64) { /* special dummy frames */ |
| 30 | return FRAME_SKIPPED; |
| 31 | } |
| 32 | |
| 33 | /* picture header */ |
| 34 | if (get_bits_long(&s->gb, 22) != 0x20) { |
| 35 | av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n"); |
| 36 | return -1; |
| 37 | } |
| 38 | s->picture_number = get_bits(&s->gb, 8); /* picture timestamp */ |
| 39 | |
| 40 | if (get_bits1(&s->gb) != 1) { |
| 41 | av_log(s->avctx, AV_LOG_ERROR, "Bad marker\n"); |
| 42 | return -1; /* marker */ |
| 43 | } |
| 44 | if (get_bits1(&s->gb) != 0) { |
| 45 | av_log(s->avctx, AV_LOG_ERROR, "Bad H263 id\n"); |
| 46 | return -1; /* h263 id */ |
| 47 | } |
| 48 | skip_bits1(&s->gb); /* split screen off */ |
| 49 | skip_bits1(&s->gb); /* camera off */ |
| 50 | skip_bits1(&s->gb); /* freeze picture release off */ |
| 51 | |
| 52 | format = get_bits(&s->gb, 3); |
| 53 | if (format == 0 || format == 6) { |
| 54 | av_log(s->avctx, AV_LOG_ERROR, "Intel H263 free format not supported\n"); |
| 55 | return -1; |
| 56 | } |
| 57 | s->h263_plus = 0; |
| 58 | |
| 59 | s->pict_type = AV_PICTURE_TYPE_I + get_bits1(&s->gb); |
| 60 | |
| 61 | s->h263_long_vectors = get_bits1(&s->gb); |
| 62 | |
| 63 | if (get_bits1(&s->gb) != 0) { |
| 64 | av_log(s->avctx, AV_LOG_ERROR, "SAC not supported\n"); |
| 65 | return -1; /* SAC: off */ |
| 66 | } |
| 67 | s->obmc= get_bits1(&s->gb); |
| 68 | s->unrestricted_mv = s->obmc || s->h263_long_vectors; |
| 69 | s->pb_frame = get_bits1(&s->gb); |
| 70 | |
| 71 | if (format < 6) { |
| 72 | s->width = ff_h263_format[format][0]; |
| 73 | s->height = ff_h263_format[format][1]; |
| 74 | s->avctx->sample_aspect_ratio.num = 12; |
| 75 | s->avctx->sample_aspect_ratio.den = 11; |
| 76 | } else { |
| 77 | format = get_bits(&s->gb, 3); |
| 78 | if(format == 0 || format == 7){ |
| 79 | av_log(s->avctx, AV_LOG_ERROR, "Wrong Intel H263 format\n"); |
| 80 | return -1; |
| 81 | } |
| 82 | if(get_bits(&s->gb, 2)) |
| 83 | av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n"); |
| 84 | s->loop_filter = get_bits1(&s->gb) * !s->avctx->lowres; |
| 85 | if(get_bits1(&s->gb)) |
| 86 | av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n"); |
| 87 | if(get_bits1(&s->gb)) |
| 88 | s->pb_frame = 2; |
| 89 | if(get_bits(&s->gb, 5)) |
| 90 | av_log(s->avctx, AV_LOG_ERROR, "Bad value for reserved field\n"); |
| 91 | if(get_bits(&s->gb, 5) != 1) |
| 92 | av_log(s->avctx, AV_LOG_ERROR, "Invalid marker\n"); |
| 93 | } |
| 94 | if(format == 6){ |
| 95 | int ar = get_bits(&s->gb, 4); |
| 96 | skip_bits(&s->gb, 9); // display width |
| 97 | skip_bits1(&s->gb); |
| 98 | skip_bits(&s->gb, 9); // display height |
| 99 | if(ar == 15){ |
| 100 | s->avctx->sample_aspect_ratio.num = get_bits(&s->gb, 8); // aspect ratio - width |
| 101 | s->avctx->sample_aspect_ratio.den = get_bits(&s->gb, 8); // aspect ratio - height |
| 102 | } else { |
| 103 | s->avctx->sample_aspect_ratio = ff_h263_pixel_aspect[ar]; |
| 104 | } |
| 105 | if (s->avctx->sample_aspect_ratio.num == 0) |
| 106 | av_log(s->avctx, AV_LOG_ERROR, "Invalid aspect ratio.\n"); |
| 107 | } |
| 108 | |
| 109 | s->chroma_qscale= s->qscale = get_bits(&s->gb, 5); |
| 110 | skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */ |
| 111 | |
| 112 | if(s->pb_frame){ |
| 113 | skip_bits(&s->gb, 3); //temporal reference for B-frame |
| 114 | skip_bits(&s->gb, 2); //dbquant |
| 115 | } |
| 116 | |
| 117 | /* PEI */ |
| 118 | if (skip_1stop_8data_bits(&s->gb) < 0) |
| 119 | return AVERROR_INVALIDDATA; |
| 120 | s->f_code = 1; |
| 121 | |
| 122 | s->y_dc_scale_table= |
| 123 | s->c_dc_scale_table= ff_mpeg1_dc_scale_table; |
| 124 | |
| 125 | ff_h263_show_pict_info(s); |
| 126 | |
| 127 | return 0; |
| 128 | } |
| 129 | |
| 130 | AVCodec ff_h263i_decoder = { |
| 131 | .name = "h263i", |
| 132 | .long_name = NULL_IF_CONFIG_SMALL("Intel H.263"), |
| 133 | .type = AVMEDIA_TYPE_VIDEO, |
| 134 | .id = AV_CODEC_ID_H263I, |
| 135 | .priv_data_size = sizeof(MpegEncContext), |
| 136 | .init = ff_h263_decode_init, |
| 137 | .close = ff_h263_decode_end, |
| 138 | .decode = ff_h263_decode_frame, |
| 139 | .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1, |
| 140 | .pix_fmts = (const enum AVPixelFormat[]) { |
| 141 | AV_PIX_FMT_YUV420P, |
| 142 | AV_PIX_FMT_NONE |
| 143 | }, |
| 144 | }; |