* @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
* 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.
#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
*/
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;
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");
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++) {
}
-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);
} 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,
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;
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;
}
* @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
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;
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)
{
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)
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;
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
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++;
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++;
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