libavformat/avs.c

   1 /*
   2  * AVS demuxer.
   3  * Copyright (c) 2006  Aurelien Jacobs <aurel@gnuage.org>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "avformat.h"
  23 #include "voc.h"
  24
  25
  26 typedef struct avs_format {
  27     voc_dec_context_t voc;
  28     AVStream *st_video;
  29     AVStream *st_audio;
  30     int width;
  31     int height;
  32     int bits_per_sample;
  33     int fps;
  34     int nb_frames;
  35     int remaining_frame_size;
  36     int remaining_audio_size;
  37 } avs_format_t;
  38
  39 typedef enum avs_block_type {
  40     AVS_NONE      = 0x00,
  41     AVS_VIDEO     = 0x01,
  42     AVS_AUDIO     = 0x02,
  43     AVS_PALETTE   = 0x03,
  44     AVS_GAME_DATA = 0x04,
  45 } avs_block_type_t;
  46
  47 static int avs_probe(AVProbeData * p)
  48 {
  49     const uint8_t *d;
  50
  51     d = p->buf;
  52     if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
  53         return 50;
  54
  55     return 0;
  56 }
  57
  58 static int avs_read_header(AVFormatContext * s, AVFormatParameters * ap)
  59 {
  60     avs_format_t *avs = s->priv_data;
  61
  62     s->ctx_flags |= AVFMTCTX_NOHEADER;
  63
  64     url_fskip(s->pb, 4);
  65     avs->width = get_le16(s->pb);
  66     avs->height = get_le16(s->pb);
  67     avs->bits_per_sample = get_le16(s->pb);
  68     avs->fps = get_le16(s->pb);
  69     avs->nb_frames = get_le32(s->pb);
  70     avs->remaining_frame_size = 0;
  71     avs->remaining_audio_size = 0;
  72
  73     avs->st_video = avs->st_audio = NULL;
  74
  75     if (avs->width != 318 || avs->height != 198)
  76         av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
  77                "when the avs format is supposed to be 318x198 only.\n",
  78                avs->width, avs->height);
  79
  80     return 0;
  81 }
  82
  83 static int
  84 avs_read_video_packet(AVFormatContext * s, AVPacket * pkt,
  85                       avs_block_type_t type, int sub_type, int size,
  86                       uint8_t * palette, int palette_size)
  87 {
  88     avs_format_t *avs = s->priv_data;
  89     int ret;
  90
  91     ret = av_new_packet(pkt, size + palette_size);
  92     if (ret < 0)
  93         return ret;
  94
  95     if (palette_size) {
  96         pkt->data[0] = 0x00;
  97         pkt->data[1] = 0x03;
  98         pkt->data[2] = palette_size & 0xFF;
  99         pkt->data[3] = (palette_size >> 8) & 0xFF;
 100         memcpy(pkt->data + 4, palette, palette_size - 4);
 101     }
 102
 103     pkt->data[palette_size + 0] = sub_type;
 104     pkt->data[palette_size + 1] = type;
 105     pkt->data[palette_size + 2] = size & 0xFF;
 106     pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
 107     ret = get_buffer(s->pb, pkt->data + palette_size + 4, size - 4) + 4;
 108     if (ret < size) {
 109         av_free_packet(pkt);
 110         return AVERROR(EIO);
 111     }
 112
 113     pkt->size = ret + palette_size;
 114     pkt->stream_index = avs->st_video->index;
 115     if (sub_type == 0)
 116         pkt->flags |= PKT_FLAG_KEY;
 117
 118     return 0;
 119 }
 120
 121 static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
 122 {
 123     avs_format_t *avs = s->priv_data;
 124     int ret, size;
 125
 126     size = url_ftell(s->pb);
 127     ret = voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
 128     size = url_ftell(s->pb) - size;
 129     avs->remaining_audio_size -= size;
 130
 131     if (ret == AVERROR(EIO))
 132         return 0;    /* this indicate EOS */
 133     if (ret < 0)
 134         return ret;
 135
 136     pkt->stream_index = avs->st_audio->index;
 137     pkt->flags |= PKT_FLAG_KEY;
 138
 139     return size;
 140 }
 141
 142 static int avs_read_packet(AVFormatContext * s, AVPacket * pkt)
 143 {
 144     avs_format_t *avs = s->priv_data;
 145     int sub_type = 0, size = 0;
 146     avs_block_type_t type = AVS_NONE;
 147     int palette_size = 0;
 148     uint8_t palette[4 + 3 * 256];
 149     int ret;
 150
 151     if (avs->remaining_audio_size > 0)
 152         if (avs_read_audio_packet(s, pkt) > 0)
 153             return 0;
 154
 155     while (1) {
 156         if (avs->remaining_frame_size <= 0) {
 157             if (!get_le16(s->pb))    /* found EOF */
 158                 return AVERROR(EIO);
 159             avs->remaining_frame_size = get_le16(s->pb) - 4;
 160         }
 161
 162         while (avs->remaining_frame_size > 0) {
 163             sub_type = get_byte(s->pb);
 164             type = get_byte(s->pb);
 165             size = get_le16(s->pb);
 166             avs->remaining_frame_size -= size;
 167
 168             switch (type) {
 169             case AVS_PALETTE:
 170                 ret = get_buffer(s->pb, palette, size - 4);
 171                 if (ret < size - 4)
 172                     return AVERROR(EIO);
 173                 palette_size = size;
 174                 break;
 175
 176             case AVS_VIDEO:
 177                 if (!avs->st_video) {
 178                     avs->st_video = av_new_stream(s, AVS_VIDEO);
 179                     if (avs->st_video == NULL)
 180                         return AVERROR(ENOMEM);
 181                     avs->st_video->codec->codec_type = CODEC_TYPE_VIDEO;
 182                     avs->st_video->codec->codec_id = CODEC_ID_AVS;
 183                     avs->st_video->codec->width = avs->width;
 184                     avs->st_video->codec->height = avs->height;
 185                     avs->st_video->codec->bits_per_sample=avs->bits_per_sample;
 186                     avs->st_video->nb_frames = avs->nb_frames;
 187                     avs->st_video->codec->time_base = (AVRational) {
 188                     1, avs->fps};
 189                 }
 190                 return avs_read_video_packet(s, pkt, type, sub_type, size,
 191                                              palette, palette_size);
 192
 193             case AVS_AUDIO:
 194                 if (!avs->st_audio) {
 195                     avs->st_audio = av_new_stream(s, AVS_AUDIO);
 196                     if (avs->st_audio == NULL)
 197                         return AVERROR(ENOMEM);
 198                     avs->st_audio->codec->codec_type = CODEC_TYPE_AUDIO;
 199                 }
 200                 avs->remaining_audio_size = size - 4;
 201                 size = avs_read_audio_packet(s, pkt);
 202                 if (size != 0)
 203                     return size;
 204                 break;
 205
 206             default:
 207                 url_fskip(s->pb, size - 4);
 208             }
 209         }
 210     }
 211 }
 212
 213 static int avs_read_close(AVFormatContext * s)
 214 {
 215     return 0;
 216 }
 217
 218 AVInputFormat avs_demuxer = {
 219     "avs",
 220     NULL_IF_CONFIG_SMALL("AVS format"),
 221     sizeof(avs_format_t),
 222     avs_probe,
 223     avs_read_header,
 224     avs_read_packet,
 225     avs_read_close,
 226 };