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Lawrence D'Oliveiro committed Dec 31, 2009
1 parent 38523b8 commit 1fc1cf3
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Showing 3 changed files with 36 additions and 31 deletions.
6 changes: 3 additions & 3 deletions src/da-internal.h
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Original file line number Diff line number Diff line change
Expand Up @@ -86,9 +86,9 @@ struct source { /* describes an input video file */
struct vob *vob; /* containing vob */
};

struct audpts {
pts_t pts[2];
int asect;
struct audpts { /* describes a packet in an audio stream */
pts_t pts[2]; /* start and end time of packet */
int asect; /* sector number in source file */
};

struct audchannel {
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4 changes: 1 addition & 3 deletions src/dvdauthor.c
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Original file line number Diff line number Diff line change
Expand Up @@ -703,7 +703,7 @@ static void setattr
{
pgc->subpmap[l][m] = 128 + k;
used = 1; // keep looping in case it's referenced multiple times
} /*if; for; for */
} /*if; for; for*/
if (used)
continue;
// Find a subpicture slot that is not used
Expand Down Expand Up @@ -738,7 +738,6 @@ handled: ;
for (l = 0; l < 32; l++)
{
int mainid = -1;

for (m = 0; m < 4; m++)
{
if ((mask & 1 << m) == 0 && (pgc->subpmap[l][m] & 128) == 128)
Expand Down Expand Up @@ -794,7 +793,6 @@ handled: ;
for (i = 0; i < 32; i++)
{
int j, k, fnd;

fnd = 0;
for (j = 0; j < va->numallpgcs; j++)
for (k = 0; k < 4; k++)
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57 changes: 32 additions & 25 deletions src/dvdvob.c
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Original file line number Diff line number Diff line change
Expand Up @@ -798,7 +798,8 @@ static void printvobustatus(struct vobgroup *va,int cursect)
fprintf(stderr,"STAT: VOBU %d at %dMB, %d PGCs\r",nv,cursect/512,va->numallpgcs);
}

static void audio_scan_ac3(struct audchannel *ach,unsigned char *buf,int sof,int len)
static void audio_scan_ac3(struct audchannel *ach,const unsigned char *buf,int sof,int len)
/* gets information about AC3 audio. */
{
uint32_t parse;
int acmod,lfeon,nch=0;
Expand All @@ -813,6 +814,7 @@ static void audio_scan_ac3(struct audchannel *ach,unsigned char *buf,int sof,int
fprintf(stderr,"WARN: Unknown AC3 sample rate: %d\n",parse>>30);
}
audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_SAMPLERATE,"48khz");
/* now figure out how many channels are present ... (yes, all this code) */
parse<<=8;
// check bsid
if( (parse>>27)!=8 && (parse>>27)!=6 ) // must be v6 or v8
Expand All @@ -823,23 +825,19 @@ static void audio_scan_ac3(struct audchannel *ach,unsigned char *buf,int sof,int
// acmod gives # of channels
acmod=(parse>>29);
parse<<=3;
// skip cmixlev?
if( (acmod&1) && (acmod!=1) )
parse<<=2;
// skip surmixlev?
if( acmod&4 )
parse<<=2;
// dsurmod
if( acmod==2 ) {
if( (parse>>30)==2 )
if( (acmod&1) && (acmod!=1) ) /* centre channel present */
parse<<=2; /* skip cmixlev */
if( acmod&4 ) /* surround channel(s) present */
parse<<=2; /* skip surmixlev */
if( acmod==2 ) { /* simple stereo */
/* process dsurmod */
if( (parse>>30)==2 ) /* 2 => Dolby Surround encoded, 1 => not encoded, 0 => not indicated, 3 => reserved */
audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_DOLBY,"surround");
// else if( (parse>>30)==1 )
// audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_DOLBY,"nosurround");
parse<<=2;
}
// lfeon
lfeon=(parse>>31);

lfeon=(parse>>31); /* low-frequency effects on */
// calc # channels
switch(acmod) {
case 0: nch=2; break;
Expand All @@ -851,37 +849,40 @@ static void audio_scan_ac3(struct audchannel *ach,unsigned char *buf,int sof,int
case 6: nch=4; break;
case 7: nch=5; break;
}
if( lfeon ) nch++;
if( lfeon ) nch++; /* include LFE channel */
sprintf(attr,"%dch",nch);
audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_CHANNELS,attr);
}

static void audio_scan_dts(struct audchannel *ach,unsigned char *buf,int sof,int len)
static void audio_scan_dts(struct audchannel *ach,const unsigned char *buf,int sof,int len)
/* gets information about DTS audio. */
{
/* can't do anything */
/* could determine number of channels and sampling rate, but I'm not bothering for now */
}

static void audio_scan_pcm(struct audchannel *ach,unsigned char *buf,int len)
static void audio_scan_pcm(struct audchannel *ach,const unsigned char *buf,int len)
/* gets information about LPCM audio. */
{
char attr[6];

switch(buf[1]>>6) {
case 0: audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_QUANT,"16bps"); break;
case 1: audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_QUANT,"20bps"); break;
case 2: audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_QUANT,"24bps"); break;
/* case 3: illegal */
}
sprintf(attr,"%dkhz",48*(1+((buf[1]>>4)&1)));
sprintf(attr,"%dkhz",48*(1+((buf[1]>>4)&1))); /* 48 or 96kHz */
audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_SAMPLERATE,attr);
sprintf(attr,"%dch",(buf[1]&7)+1);
sprintf(attr,"%dch",(buf[1]&7)+1); /* nr channels */
audiodesc_set_audio_attr(&ach->ad,&ach->adwarn,AUDIO_CHANNELS,attr);
}

int FindVobus(const char *fbase,struct vobgroup *va,int ismenu)
/* generates output VOB files for a menu or titleset. ismenu = 0 for a titleset, 1 for a VTS menu, 2 for a VMG menu. */
{
unsigned char *buf;
int cursect=0;
int fsect=-1; /* sector nr in current output VOB file */
int cursect=0; /* sector nr in input file */
int fsect=-1; /* sector nr in current output VOB file, -ve => not opened yet */
int vnum;
int outnum = -ismenu + 1; /* +ve for a titleset, in which case used to generate output VOB file names */
int vobid=0;
Expand Down Expand Up @@ -1260,6 +1261,9 @@ int FindVobus(const char *fbase,struct vobgroup *va,int ismenu)
{
const int sid = buf[dptr]; /* sub-stream ID */
const int offs = read2(buf + dptr + 2);
/* offset to audio sample frame which corresponds to PTS value */
const int nrframes = buf[dptr + 1];
/* nr audio sample frames beginning in this packet */
switch (sid & 0xf8)
{
case 0x20: // subpicture
Expand All @@ -1269,16 +1273,17 @@ int FindVobus(const char *fbase,struct vobgroup *va,int ismenu)
audch = sid;
break;
case 0x80: // ac3 audio
pts1 += 2880 * buf[dptr + 1];
pts1 += 2880 * nrframes;
audch = sid & 7;
audio_scan_ac3(&thisvob->audch[audch], buf + dptr + 4, offs - 1, endop - (dptr + 4));
break;
case 0x88: // dts audio
/* pts1 += 960 * nrframes; */ /* why not? */
audch = 24 | (sid & 7);
audio_scan_dts(&thisvob->audch[audch], buf + dptr + 4, offs - 1, endop - (dptr + 4));
break;
case 0xa0: // pcm audio
pts1 += 150 * buf[dptr + 1];
pts1 += 150 * nrframes;
audch = 16 | (sid & 7);
audio_scan_pcm(&thisvob->audch[audch], buf + dptr + 4, endop - (dptr + 4));
break;
Expand Down Expand Up @@ -1307,7 +1312,7 @@ int FindVobus(const char *fbase,struct vobgroup *va,int ismenu)
continue;
} /*if*/
if (mp2hdr[index].hdrptr < 0)
backpts1 += 2160;
backpts1 += 2160; /* how much time to add to end of previous packet */
else
pts1 += 2160;
mp2hdr[index].hdrptr += mpa_len(h); /* to next header */
Expand All @@ -1316,6 +1321,7 @@ int FindVobus(const char *fbase,struct vobgroup *va,int ismenu)
memcpy(mp2hdr[index].buf, buf + dptr + len - 3, 3);
audiodesc_set_audio_attr(&thisvob->audch[audch].ad, &thisvob->audch[audch]. adwarn, AUDIO_SAMPLERATE, "48khz");
} /*if*/
/* at this point, pts1 is the duration of the audio in the packet */
if (haspts)
{
pts0 = readpts(buf + 23);
Expand All @@ -1330,6 +1336,7 @@ int FindVobus(const char *fbase,struct vobgroup *va,int ismenu)
if (audch < 0 || audch >= 64)
{
fprintf(stderr,"WARN: Invalid audio channel %d\n",audch);
/* and ignore */
}
else if (haspts)
{
Expand Down Expand Up @@ -1359,7 +1366,7 @@ int FindVobus(const char *fbase,struct vobgroup *va,int ismenu)

if (ach->audpts[ach->numaudpts - 1].pts[1] < pts0) {
if (audch >= 32)
goto noshow;
goto noshow; /* not audio */
fprintf(stderr, "WARN: Discontinuity of %" PRId64" in audio channel %d; please remultiplex input.\n", pts0 - ach->audpts[ach->numaudpts - 1].pts[1], audch);
// fprintf(stderr,"last=%d, this=%d\n",ach->audpts[ach->numaudpts-1].pts[1],pts0);
} else if (ach->audpts[ach->numaudpts - 1].pts[1] > pts0)
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