virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00
Code Issues Releases Activity

minor VMD system update; still not perfect, but should not crash either

Browse Source 
Originally committed as revision 2887 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Mike Melanson 2004-03-14 04:08:11 +00:00
parent 3a278992bd
commit 23fe14bb20
2 changed files with 144 additions and 45 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

81
libavcodec/vmdav.c
View File

@ -22,6 +22,8 @@
* @file vmdvideo.c
* Sierra VMD audio & video decoders
* by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
* for more information on the Sierra VMD format, visit:
* http://www.pcisys.net/~melanson/codecs/
*
* The video decoder outputs PAL8 colorspace data. The decoder expects
* a 0x330-byte VMD file header to be transmitted via extradata during
@ -30,7 +32,7 @@
* information record from the VMD file.
*
* The audio decoder, like the video decoder, expects each encoded data
* chunk to be prepended with the approriate 16-byte frame information
* chunk to be prepended with the appropriate 16-byte frame information
* record from the VMD file. It does not require the 0x330-byte VMD file
* header, but it does need the audio setup parameters passed in through
* normal libavcodec API means.
@ -51,12 +53,6 @@
#define VMD_HEADER_SIZE 0x330
#define PALETTE_COUNT 256
#define LE_16(x) ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
#define LE_32(x) ((((uint8_t*)(x))[3] << 24) | \
(((uint8_t*)(x))[2] << 16) | \
(((uint8_t*)(x))[1] << 8) | \
((uint8_t*)(x))[0])
/*
* Video Decoder
*/
@ -275,7 +271,7 @@ static void vmd_decode(VmdVideoContext *s)
if (len & 0x80) {
len = (len & 0x7F) + 1;
if (*pb++ == 0xFF)
len = rle_unpack(pb, dp, len);
len = rle_unpack(pb, &dp[ofs], len);
else
memcpy(&dp[ofs], pb, len);
pb += len;
@ -349,6 +345,9 @@ static int vmdvideo_decode_frame(AVCodecContext *avctx,
s->buf = buf;
s->size = buf_size;
if (buf_size < 16)
return buf_size;
s->frame.reference = 1;
if (avctx->get_buffer(avctx, &s->frame)) {
printf (" VMD Video: get_buffer() failed\n");
@ -408,8 +407,8 @@ static int vmdaudio_decode_init(AVCodecContext *avctx)
s->bits = avctx->bits_per_sample;
s->block_align = avctx->block_align;
printf (" %d channels, %d bits/sample, block align = %d\n",
s->channels, s->bits, s->block_align);
printf (" %d channels, %d bits/sample, block align = %d, sample rate = %d\n",
s->channels, s->bits, s->block_align, avctx->sample_rate);
/* set up the steps8 and steps16 tables */
for (i = 0; i < 8; i++) {
@ -460,10 +459,17 @@ static void vmdaudio_decode_audio(VmdAudioContext *s, unsigned char *data,
}
static void vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data,
static int vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data,
uint8_t *buf, int silence)
{
int bytes_decoded = 0;
int i;
if (silence)
printf (" silent block!\n");
if (s->channels == 2) {
/* stereo handling */
if ((s->block_align & 0x01) == 0) {
if (silence)
memset(data, 0, s->block_align * 2);
@ -472,11 +478,34 @@ static void vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data,
} else {
if (silence)
memset(data, 0, s->block_align * 2);
// else
// vmdaudio_decode_audio(s, data, buf, 1);
else
vmdaudio_decode_audio(s, data, buf, 1);
}
} else {
/* mono handling */
if (silence) {
if (s->bits == 16) {
memset(data, 0, s->block_align * 2);
bytes_decoded = s->block_align * 2;
} else {
// memset(data, 0x00, s->block_align);
// bytes_decoded = s->block_align;
memset(data, 0x00, s->block_align * 2);
bytes_decoded = s->block_align * 2;
}
} else {
if (s->bits == 16) {
} else {
/* copy the data but convert it to signed */
for (i = 0; i < s->block_align; i++)
data[i * 2 + 1] = buf[i] + 0x80;
bytes_decoded = s->block_align * 2;
}
}
}
return bytes_decoded;
}
static int vmdaudio_decode_frame(AVCodecContext *avctx,
@ -491,10 +520,16 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx,
unsigned char *p = buf + 16;
unsigned char *p_end = buf + buf_size;
printf (" processing audio frame with %d bytes\n", buf_size);
if (buf_size < 16)
return buf_size;
*data_size = 0;
if (buf[6] == 1) {
/* the chunk contains audio */
vmdaudio_loadsound(s, output_samples, p, 0);
*data_size = vmdaudio_loadsound(s, output_samples, p, 0);
} else if (buf[6] == 2) {
printf (" hey! audio case #2\n");
/* the chunk contains audio and silence mixed together */
sound_flags = LE_32(p);
p += 4;
@ -503,22 +538,24 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx,
while (p < p_end) {
if (sound_flags & 0x01)
/* audio */
vmdaudio_loadsound(s, output_samples, p, 1);
else
/* silence */
vmdaudio_loadsound(s, output_samples, p, 0);
p += s->block_align;
*data_size += vmdaudio_loadsound(s, output_samples, p, 1);
else {
/* audio */
*data_size += vmdaudio_loadsound(s, output_samples, p, 0);
p += s->block_align;
}
output_samples += (s->block_align * s->bits / 8);
sound_flags >>= 1;
}
} else if (buf[6] == 3) {
printf (" hey! audio case #3\n");
/* silent chunk */
vmdaudio_loadsound(s, output_samples, p, 1);
*data_size = vmdaudio_loadsound(s, output_samples, p, 1);
}
// *datasize = ;
printf (" final sample count = %d, byte count = %d\n", (*data_size) / 2,
*data_size);
return buf_size;
}

108
libavformat/sierravmd.c
View File

@ -21,16 +21,12 @@
* @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 LE_16(x) ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
#define LE_32(x) ((((uint8_t*)(x))[3] << 24) | \
(((uint8_t*)(x))[2] << 16) | \
(((uint8_t*)(x))[1] << 8) | \
((uint8_t*)(x))[0])
#define VMD_HEADER_SIZE 0x0330
#define BYTES_PER_FRAME_RECORD 16
@ -56,6 +52,11 @@ typedef struct VmdDemuxContext {
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;
@ -73,6 +74,32 @@ static int vmd_probe(AVProbeData *p)
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)
{
@ -85,15 +112,19 @@ static int vmd_read_header(AVFormatContext *s,
unsigned char *current_frame_record;
offset_t current_offset;
int i;
int sample_rate;
unsigned int total_frames;
int video_frame_count = 0;
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 -EIO;
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)
@ -109,8 +140,8 @@ int video_frame_count = 0;
memcpy(st->codec.extradata, vmd->vmd_header, VMD_HEADER_SIZE);
/* if sample rate is 0, assume no audio */
sample_rate = LE_16(&vmd->vmd_header[804]);
if (sample_rate) {
vmd->sample_rate = LE_16(&vmd->vmd_header[804]);
if (vmd->sample_rate) {
st = av_new_stream(s, 0);
if (!st)
return AVERROR_NOMEM;
@ -119,15 +150,28 @@ int video_frame_count = 0;
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 = sample_rate;
st->codec.bit_rate = st->codec.sample_rate *
st->codec.bits_per_sample * st->codec.channels;
st->codec.block_align = LE_16(&vmd->vmd_header[806]);
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 = 8;
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
@ -184,12 +228,14 @@ int video_frame_count = 0;
memcpy(vmd->frame_table[i].frame_record, current_frame_record,
BYTES_PER_FRAME_RECORD);
if (current_frame_record[0] == 0x02) {
/* assume 15 fps for now */
vmd->frame_table[i].pts = video_frame_count++;
vmd->frame_table[i].pts *= 90000;
vmd->frame_table[i].pts /= 15;
}
/* 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++;
@ -227,10 +273,26 @@ static int vmd_read_packet(AVFormatContext *s,
ret = get_buffer(pb, pkt->data + BYTES_PER_FRAME_RECORD,
frame->frame_size);
if (ret != frame->frame_size)
if (ret != frame->frame_size) {
av_free_packet(pkt);
ret = -EIO;
}
pkt->stream_index = frame->stream_index;
pkt->pts = frame->pts;
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++;