ffmpeg/libavformat/avs.c

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/*
* AVS demuxer.
* Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
*
* 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include "voc.h"
typedef struct avs_format {
voc_dec_context_t voc;
AVStream *st_video;
AVStream *st_audio;
int width;
int height;
int bits_per_sample;
int fps;
int nb_frames;
int remaining_frame_size;
int remaining_audio_size;
} avs_format_t;
typedef enum avs_block_type {
AVS_VIDEO = 0x01,
AVS_AUDIO = 0x02,
AVS_PALETTE = 0x03,
AVS_GAME_DATA = 0x04,
} avs_block_type_t;
static int avs_probe(AVProbeData * p)
{
const uint8_t *d;
if (p->buf_size < 2)
return 0;
d = p->buf;
if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
return 50;
return 0;
}
static int avs_read_header(AVFormatContext * s, AVFormatParameters * ap)
{
avs_format_t *avs = s->priv_data;
s->ctx_flags |= AVFMTCTX_NOHEADER;
url_fskip(&s->pb, 4);
avs->width = get_le16(&s->pb);
avs->height = get_le16(&s->pb);
avs->bits_per_sample = get_le16(&s->pb);
avs->fps = get_le16(&s->pb);
avs->nb_frames = get_le32(&s->pb);
avs->remaining_frame_size = 0;
avs->remaining_audio_size = 0;
avs->st_video = avs->st_audio = NULL;
if (avs->width != 318 || avs->height != 198)
av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
"when the avs format is supposed to be 318x198 only.\n",
avs->width, avs->height);
return 0;
}
static int
avs_read_video_packet(AVFormatContext * s, AVPacket * pkt,
avs_block_type_t type, int sub_type, int size,
uint8_t * palette, int palette_size)
{
avs_format_t *avs = s->priv_data;
int ret;
ret = av_new_packet(pkt, size + palette_size);
if (ret < 0)
return ret;
if (palette_size) {
pkt->data[0] = 0x00;
pkt->data[1] = 0x03;
pkt->data[2] = palette_size & 0xFF;
pkt->data[3] = (palette_size >> 8) & 0xFF;
memcpy(pkt->data + 4, palette, palette_size - 4);
}
pkt->data[palette_size + 0] = sub_type;
pkt->data[palette_size + 1] = type;
pkt->data[palette_size + 2] = size & 0xFF;
pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
ret = get_buffer(&s->pb, pkt->data + palette_size + 4, size - 4) + 4;
if (ret < size) {
av_free_packet(pkt);
return AVERROR_IO;
}
pkt->size = ret + palette_size;
pkt->stream_index = avs->st_video->index;
if (sub_type == 0)
pkt->flags |= PKT_FLAG_KEY;
return 0;
}
static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
{
avs_format_t *avs = s->priv_data;
int ret, size;
size = url_ftell(&s->pb);
ret = voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
size = url_ftell(&s->pb) - size;
avs->remaining_audio_size -= size;
if (ret == AVERROR_IO)
return 0; /* this indicate EOS */
if (ret < 0)
return ret;
pkt->stream_index = avs->st_audio->index;
pkt->flags |= PKT_FLAG_KEY;
return size;
}
static int avs_read_packet(AVFormatContext * s, AVPacket * pkt)
{
avs_format_t *avs = s->priv_data;
int sub_type = 0, size = 0;
avs_block_type_t type = 0;
int palette_size = 0;
uint8_t palette[4 + 3 * 256];
int ret;
if (avs->remaining_audio_size > 0)
if (avs_read_audio_packet(s, pkt) > 0)
return 0;
while (1) {
if (avs->remaining_frame_size <= 0) {
if (!get_le16(&s->pb)) /* found EOF */
return AVERROR_IO;
avs->remaining_frame_size = get_le16(&s->pb) - 4;
}
while (avs->remaining_frame_size > 0) {
sub_type = get_byte(&s->pb);
type = get_byte(&s->pb);
size = get_le16(&s->pb);
avs->remaining_frame_size -= size;
switch (type) {
case AVS_PALETTE:
ret = get_buffer(&s->pb, palette, size - 4);
if (ret < size - 4)
return AVERROR_IO;
palette_size = size;
break;
case AVS_VIDEO:
if (!avs->st_video) {
avs->st_video = av_new_stream(s, AVS_VIDEO);
if (avs->st_video == NULL)
return AVERROR_NOMEM;
avs->st_video->codec->codec_type = CODEC_TYPE_VIDEO;
avs->st_video->codec->codec_id = CODEC_ID_AVS;
avs->st_video->codec->width = avs->width;
avs->st_video->codec->height = avs->height;
avs->st_video->codec->bits_per_sample=avs->bits_per_sample;
avs->st_video->nb_frames = avs->nb_frames;
avs->st_video->codec->time_base = (AVRational) {
1, avs->fps};
}
return avs_read_video_packet(s, pkt, type, sub_type, size,
palette, palette_size);
case AVS_AUDIO:
if (!avs->st_audio) {
avs->st_audio = av_new_stream(s, AVS_AUDIO);
if (avs->st_audio == NULL)
return AVERROR_NOMEM;
avs->st_audio->codec->codec_type = CODEC_TYPE_AUDIO;
}
avs->remaining_audio_size = size - 4;
size = avs_read_audio_packet(s, pkt);
if (size != 0)
return size;
break;
default:
url_fskip(&s->pb, size - 4);
}
}
}
}
static int avs_read_close(AVFormatContext * s)
{
return 0;
}
AVInputFormat avs_demuxer = {
"avs",
"avs format",
sizeof(avs_format_t),
avs_probe,
avs_read_header,
avs_read_packet,
avs_read_close,
};