mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
323 lines
10 KiB
323 lines
10 KiB
/* |
|
* Sierra VMD Format Demuxer |
|
* Copyright (c) 2004 The ffmpeg Project |
|
* |
|
* This library 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 of the License, or (at your option) any later version. |
|
* |
|
* This library 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 this library; if not, write to the Free Software |
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
|
*/ |
|
|
|
/** |
|
* @file sierravmd.c |
|
* Sierra VMD file demuxer |
|
* by Vladimir "VAG" Gneushev (vagsoft at mail.ru) |
|
* for more information on the Sierra VMD file format, visit: |
|
* http://www.pcisys.net/~melanson/codecs/ |
|
*/ |
|
|
|
#include "avformat.h" |
|
|
|
#define VMD_HEADER_SIZE 0x0330 |
|
#define BYTES_PER_FRAME_RECORD 16 |
|
|
|
typedef struct { |
|
int stream_index; |
|
offset_t frame_offset; |
|
unsigned int frame_size; |
|
int64_t pts; |
|
int keyframe; |
|
unsigned char frame_record[BYTES_PER_FRAME_RECORD]; |
|
} vmd_frame_t; |
|
|
|
typedef struct VmdDemuxContext { |
|
int video_stream_index; |
|
int audio_stream_index; |
|
|
|
unsigned int audio_type; |
|
unsigned int audio_samplerate; |
|
unsigned int audio_bits; |
|
unsigned int audio_channels; |
|
|
|
unsigned int frame_count; |
|
vmd_frame_t *frame_table; |
|
unsigned int current_frame; |
|
|
|
int sample_rate; |
|
int64_t audio_sample_counter; |
|
int audio_frame_divisor; |
|
int audio_block_align; |
|
|
|
unsigned char vmd_header[VMD_HEADER_SIZE]; |
|
} VmdDemuxContext; |
|
|
|
static int vmd_probe(AVProbeData *p) |
|
{ |
|
if (p->buf_size < 2) |
|
return 0; |
|
|
|
/* check if the first 2 bytes of the file contain the appropriate size |
|
* of a VMD header chunk */ |
|
if (LE_16(&p->buf[0]) != VMD_HEADER_SIZE - 2) |
|
return 0; |
|
|
|
/* only return half certainty since this check is a bit sketchy */ |
|
return AVPROBE_SCORE_MAX / 2; |
|
} |
|
|
|
/* This is a support function to determine the duration, in sample |
|
* frames, of a particular audio chunk, taking into account silent |
|
* encodings. */ |
|
static int vmd_calculate_audio_duration(unsigned char *audio_chunk, |
|
int audio_chunk_size, int block_align) |
|
{ |
|
unsigned char *p = audio_chunk + 16; |
|
unsigned char *p_end = audio_chunk + audio_chunk_size; |
|
int total_samples = 0; |
|
unsigned int sound_flags; |
|
|
|
if (audio_chunk_size < 16) |
|
return 0; |
|
|
|
sound_flags = LE_32(p); |
|
p += 4; |
|
while (p < p_end) { |
|
total_samples += block_align; |
|
if ((sound_flags & 0x01) == 0) |
|
p += block_align; |
|
sound_flags >>= 1; |
|
} |
|
|
|
return total_samples; |
|
} |
|
|
|
static int vmd_read_header(AVFormatContext *s, |
|
AVFormatParameters *ap) |
|
{ |
|
VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data; |
|
ByteIOContext *pb = &s->pb; |
|
AVStream *st; |
|
unsigned int toc_offset; |
|
unsigned char *raw_frame_table; |
|
int raw_frame_table_size; |
|
unsigned char *current_frame_record; |
|
offset_t current_offset; |
|
int i; |
|
unsigned int total_frames; |
|
int64_t video_pts_inc; |
|
int64_t current_video_pts = 0; |
|
|
|
/* fetch the main header, including the 2 header length bytes */ |
|
url_fseek(pb, 0, SEEK_SET); |
|
if (get_buffer(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE) |
|
return AVERROR_IO; |
|
|
|
vmd->audio_sample_counter = 0; |
|
vmd->audio_frame_divisor = 1; |
|
vmd->audio_block_align = 1; |
|
|
|
/* start up the decoders */ |
|
st = av_new_stream(s, 0); |
|
if (!st) |
|
return AVERROR_NOMEM; |
|
av_set_pts_info(st, 33, 1, 90000); |
|
vmd->video_stream_index = st->index; |
|
st->codec.codec_type = CODEC_TYPE_VIDEO; |
|
st->codec.codec_id = CODEC_ID_VMDVIDEO; |
|
st->codec.codec_tag = 0; /* no fourcc */ |
|
st->codec.width = LE_16(&vmd->vmd_header[12]); |
|
st->codec.height = LE_16(&vmd->vmd_header[14]); |
|
st->codec.extradata_size = VMD_HEADER_SIZE; |
|
st->codec.extradata = av_malloc(VMD_HEADER_SIZE); |
|
memcpy(st->codec.extradata, vmd->vmd_header, VMD_HEADER_SIZE); |
|
|
|
/* if sample rate is 0, assume no audio */ |
|
vmd->sample_rate = LE_16(&vmd->vmd_header[804]); |
|
if (vmd->sample_rate) { |
|
st = av_new_stream(s, 0); |
|
if (!st) |
|
return AVERROR_NOMEM; |
|
av_set_pts_info(st, 33, 1, 90000); |
|
vmd->audio_stream_index = st->index; |
|
st->codec.codec_type = CODEC_TYPE_AUDIO; |
|
st->codec.codec_id = CODEC_ID_VMDAUDIO; |
|
st->codec.codec_tag = 0; /* no codec tag */ |
|
st->codec.channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1; |
|
st->codec.sample_rate = vmd->sample_rate; |
|
st->codec.block_align = vmd->audio_block_align = |
|
LE_16(&vmd->vmd_header[806]); |
|
if (st->codec.block_align & 0x8000) { |
|
st->codec.bits_per_sample = 16; |
|
st->codec.block_align = -(st->codec.block_align - 0x10000); |
|
} else |
|
st->codec.bits_per_sample = 16; |
|
// st->codec.bits_per_sample = 8; |
|
st->codec.bit_rate = st->codec.sample_rate * |
|
st->codec.bits_per_sample * st->codec.channels; |
|
|
|
/* for calculating pts */ |
|
vmd->audio_frame_divisor = st->codec.bits_per_sample / 8 / |
|
st->codec.channels; |
|
|
|
video_pts_inc = 90000; |
|
video_pts_inc *= st->codec.block_align; |
|
video_pts_inc /= st->codec.sample_rate; |
|
} else { |
|
/* if no audio, assume 10 frames/second */ |
|
video_pts_inc = 90000 / 10; |
|
} |
|
|
|
/* skip over the offset table and load the table of contents; don't |
|
* care about the offset table since demuxer will calculate those |
|
* independently */ |
|
toc_offset = LE_32(&vmd->vmd_header[812]); |
|
vmd->frame_count = LE_16(&vmd->vmd_header[6]); |
|
url_fseek(pb, toc_offset + vmd->frame_count * 6, SEEK_SET); |
|
|
|
/* each on-disk VMD frame has an audio part and a video part; demuxer |
|
* accounts them separately */ |
|
vmd->frame_count *= 2; |
|
raw_frame_table = NULL; |
|
vmd->frame_table = NULL; |
|
raw_frame_table_size = vmd->frame_count * BYTES_PER_FRAME_RECORD; |
|
raw_frame_table = av_malloc(raw_frame_table_size); |
|
vmd->frame_table = av_malloc(vmd->frame_count * sizeof(vmd_frame_t)); |
|
if (!raw_frame_table || !vmd->frame_table) { |
|
av_free(raw_frame_table); |
|
av_free(vmd->frame_table); |
|
return AVERROR_NOMEM; |
|
} |
|
if (get_buffer(pb, raw_frame_table, raw_frame_table_size) != |
|
raw_frame_table_size) { |
|
av_free(raw_frame_table); |
|
av_free(vmd->frame_table); |
|
return AVERROR_IO; |
|
} |
|
|
|
current_offset = LE_32(&vmd->vmd_header[20]); |
|
current_frame_record = raw_frame_table; |
|
total_frames = vmd->frame_count; |
|
i = 0; |
|
while (total_frames--) { |
|
|
|
/* if the frame size is 0, do not count the frame and bring the |
|
* total frame count down */ |
|
vmd->frame_table[i].frame_size = LE_32(¤t_frame_record[2]); |
|
|
|
/* this logic is present so that 0-length audio chunks are not |
|
* accounted */ |
|
if (!vmd->frame_table[i].frame_size) { |
|
vmd->frame_count--; /* one less frame to count */ |
|
current_frame_record += BYTES_PER_FRAME_RECORD; |
|
continue; |
|
} |
|
|
|
if (current_frame_record[0] == 0x02) |
|
vmd->frame_table[i].stream_index = vmd->video_stream_index; |
|
else |
|
vmd->frame_table[i].stream_index = vmd->audio_stream_index; |
|
vmd->frame_table[i].frame_offset = current_offset; |
|
current_offset += vmd->frame_table[i].frame_size; |
|
memcpy(vmd->frame_table[i].frame_record, current_frame_record, |
|
BYTES_PER_FRAME_RECORD); |
|
|
|
/* figure out the pts for this frame */ |
|
if (current_frame_record[0] == 0x02) { |
|
vmd->frame_table[i].pts = current_video_pts; |
|
current_video_pts += video_pts_inc; |
|
} else if (current_frame_record[0] == 0x01) { |
|
/* figure out the pts during the dispatch phase */ |
|
vmd->frame_table[i].pts = 0; |
|
} |
|
|
|
current_frame_record += BYTES_PER_FRAME_RECORD; |
|
i++; |
|
} |
|
|
|
av_free(raw_frame_table); |
|
|
|
vmd->current_frame = 0; |
|
|
|
return 0; |
|
} |
|
|
|
static int vmd_read_packet(AVFormatContext *s, |
|
AVPacket *pkt) |
|
{ |
|
VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data; |
|
ByteIOContext *pb = &s->pb; |
|
int ret = 0; |
|
vmd_frame_t *frame; |
|
|
|
if (vmd->current_frame >= vmd->frame_count) |
|
return AVERROR_IO; |
|
|
|
frame = &vmd->frame_table[vmd->current_frame]; |
|
/* position the stream (will probably be there already) */ |
|
url_fseek(pb, frame->frame_offset, SEEK_SET); |
|
|
|
if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD)) |
|
return AVERROR_NOMEM; |
|
memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD); |
|
ret = get_buffer(pb, pkt->data + BYTES_PER_FRAME_RECORD, |
|
frame->frame_size); |
|
|
|
if (ret != frame->frame_size) { |
|
av_free_packet(pkt); |
|
ret = AVERROR_IO; |
|
} |
|
pkt->stream_index = frame->stream_index; |
|
if (frame->frame_record[0] == 0x02) |
|
pkt->pts = frame->pts; |
|
else { |
|
pkt->pts = vmd->audio_sample_counter; |
|
pkt->pts *= 90000; |
|
pkt->pts /= vmd->sample_rate; |
|
// pkt->pts /= vmd->audio_frame_divisor; |
|
vmd->audio_sample_counter += vmd_calculate_audio_duration( |
|
pkt->data, pkt->size, vmd->audio_block_align); |
|
|
|
} |
|
printf (" dispatching %s frame with %d bytes and pts %lld (%0.1f sec)\n", |
|
(frame->frame_record[0] == 0x02) ? "video" : "audio", |
|
frame->frame_size + BYTES_PER_FRAME_RECORD, |
|
pkt->pts, (float)(pkt->pts / 90000.0)); |
|
|
|
vmd->current_frame++; |
|
|
|
return ret; |
|
} |
|
|
|
static int vmd_read_close(AVFormatContext *s) |
|
{ |
|
VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data; |
|
|
|
av_free(vmd->frame_table); |
|
|
|
return 0; |
|
} |
|
|
|
static AVInputFormat vmd_iformat = { |
|
"vmd", |
|
"Sierra VMD format", |
|
sizeof(VmdDemuxContext), |
|
vmd_probe, |
|
vmd_read_header, |
|
vmd_read_packet, |
|
vmd_read_close, |
|
}; |
|
|
|
int vmd_init(void) |
|
{ |
|
av_register_input_format(&vmd_iformat); |
|
return 0; |
|
}
|
|
|