shithub: mcfs

Info  •  Files  •  Log  •  Branches

extract raw streams

--- a/iso.c

+++ b/iso.c

@@ -4,6 +4,8 @@

 typedef struct Box Box;

 typedef struct RunSample RunSample;

+typedef struct Track Track;

+typedef struct SampleToChunk SampleToChunk;

 struct Box {

 	vlong dsz;

@@ -88,11 +90,7 @@

 		struct {

 			u32int entrycount;

-			struct {

-				u32int firstchunk;

-				u32int samplesperchunk;

-				u32int sdt;

-			}*entry;

+			SampleToChunk *entry;

 		}stsc;

 		struct {

@@ -129,6 +127,25 @@

 	vlong timeoffset;

 };

+struct Track {

+	u64int *chunkoffset;

+	u32int numchunks;

+

+	u32int *samplesize;

+	u32int numsamples;

+

+	SampleToChunk *stc;

+	u32int numstc;

+

+	int id;

+};

+

+struct SampleToChunk {

+	u32int firstchunk;

+	u32int samplesperchunk;

+	u32int sdt;

+};

+

 enum {

 	BoxUuid = 0x75756964u,

 	BoxFtyp = 0x66747970u,

@@ -146,6 +163,7 @@

 				BoxMinf = 0x6d696e66u,

 					BoxDinf = 0x64696e66u,

 					BoxStbl = 0x7374626cu,

+						BoxCtts = 0x63747473u,

 					BoxStsd = 0x73747364u,

 					BoxStts = 0x73747473u,

 					BoxStsc = 0x73747363u,

@@ -173,7 +191,7 @@

 	b->type == BoxMfhd || b->type == BoxTfhd || b->type == BoxTfdt || b->type == BoxTrun || \

 	b->type == BoxStsd || b->type == BoxStts || b->type == BoxStss || b->type == BoxTkhd || \

 	b->type == BoxElst || b->type == BoxStsc || b->type == BoxStco || b->type == BoxCo64 || \

-	b->type == BoxStsz \

+	b->type == BoxStsz || b->type == BoxCtts \

 )

 #define eBread(sz, e) if(Bread(f, d, (sz)) != (sz)){ werrstr(e); goto err; }

@@ -180,8 +198,11 @@

 static int dflag;

 static int dind;

+static int trackdump = -1;

 static u32int defsamplesize;

+static Track track;

+

 static int parsebox(Biobuf *f, Box *b, int *eof);

 #pragma varargck type "T" u32int

@@ -332,6 +353,47 @@

 	}

 }

+static void

+dumptrack(Biobuf *f)

+{

+	SampleToChunk *stc;

+	u32int si, ch, lastch;

+	u32int samplelast, sample, rawsz;

+	vlong o;

+	u8int *raw;

+	Biobuf out;

+

+	Binit(&out, 1, OWRITE);

+	raw = nil;

+	rawsz = 0;

+	sample = samplelast = 0;

+	stc = track.stc;

+	for(si = 0; si < track.numstc; si++, stc++){

+		lastch = si+1 < track.numstc ? stc[1].firstchunk : track.numchunks;

+		for(ch = stc->firstchunk-1; ch < lastch && ch < track.numchunks; ch++){

+			o = track.chunkoffset[ch];

+			if(Bseek(f, o, 0) != o)

+				sysfatal("chunk %ud: %r", ch);

+			for(; sample < samplelast+stc->samplesperchunk && sample < track.numsamples; sample++){

+				if(track.samplesize[sample] == 0)

+					break;

+				if(rawsz < track.samplesize[sample]){

+					rawsz = track.samplesize[sample] * 2;

+					raw = realloc(raw, rawsz);

+				}

+				if(Bread(f, raw, track.samplesize[sample]) != track.samplesize[sample])

+					sysfatal("chunk %ud sample %ud size %ud: %r", ch, sample, track.samplesize[sample]);

+				if(Bwrite(&out, raw, track.samplesize[sample]) != track.samplesize[sample])

+					exits(nil);

+			}

+			samplelast = sample;

+		}

+	}

+	fprint(2, "%ud samples\n", sample);

+	Bterm(&out);

+	free(raw);

+};

+

 static int

 parseboxdata(Biobuf *f, Box *b)

 {

@@ -369,6 +431,17 @@

 			if(inner.dstart+inner.dsz >= b->dstart+b->dsz)

 				break;

 		}

+		if(b->type == BoxTrak){

+			if(track.id == trackdump){

+				u = Boffset(f);

+				dumptrack(f);

+				Bseek(f, u, 0);

+			}

+			free(track.chunkoffset);

+			free(track.samplesize);

+			free(track.stc);

+			memset(&track, 0, sizeof(track));

+		}

 		dind--;

 	}else if(b->type == BoxMvhd){

 		n = b->version == 0 ? 96 : 108;

@@ -506,7 +579,7 @@

 	}else if(b->type == BoxStsc){

 		eBread(4, "entry_count");

 		b->stsc.entrycount = bu32(d);

-		b->stsc.entry = calloc(b->stsc.entrycount, sizeof(*b->stsc.entry));

+		b->stsc.entry = calloc(b->stsc.entrycount, sizeof(SampleToChunk));

 		for(u = 0; u < b->stsc.entrycount; u++){

 			eBread(4, "first_chunk");

 			b->stsc.entry[u].firstchunk = bu32(d);

@@ -515,6 +588,8 @@

 			eBread(4, "sample_description_table");

 			b->stsc.entry[u].sdt = bu32(d);

 		}

+		track.numstc = b->stsc.entrycount;

+		track.stc = b->stsc.entry;

 		printbox(b);

 	}else if(b->type == BoxStco || b->type == BoxCo64){

 		eBread(4, "entry_count");

@@ -524,6 +599,8 @@

 			eBread(b->type == BoxStco ? 4 : 8, "chunk_offset");

 			b->stco_co64.chunkoffset[u] = b->type == BoxStco ? bu32(d) : bu64(d);

 		}

+		track.numchunks = b->stco_co64.entrycount;

+		track.chunkoffset = b->stco_co64.chunkoffset;

 		printbox(b);

 	}else if(b->type == BoxStsz){

 		eBread(4, "sample_size");

@@ -536,6 +613,8 @@

 				eBread(4, "chunk_offset");

 				b->stsz.entrysize[u] = bu32(d);

 			}

+			track.numsamples = b->stsz.samplecount;

+			track.samplesize = b->stsz.entrysize;

 		}

 		printbox(b);

 	}else if(b->type == BoxTkhd){

@@ -546,6 +625,7 @@

 			b->tkhd.modtime = bu64(d);

 			eBread(8, "track_id"); /* skipping 4 reserved as well */

 			b->tkhd.trackid = bu32(d);

+			track.id = b->tkhd.trackid;

 			eBread(8, "duration");

 			b->tkhd.duration = bu64(d);

 		}else if(b->version == 0){

@@ -555,6 +635,7 @@

 			b->tkhd.modtime = bu32(d);

 			eBread(8, "track_id"); /* skipping 4 reserved as well */

 			b->tkhd.trackid = bu32(d);

+			track.id = b->tkhd.trackid;

 			eBread(4, "duration");

 			b->tkhd.duration = bu32(d);

 		}else{

@@ -651,6 +732,13 @@

 	return -1;

 }

+static void

+usage(void)

+{

+	fprint(2, "usage: iso [-d] [-t TRACK] FILE\n");

+	exits("usage");

+}

+

 int

 main(int argc, char **argv)

 {

@@ -662,6 +750,9 @@

 	ARGBEGIN{

 	case 'd':

 		dflag = 1;

+		break;

+	case 't':

+		trackdump = atoi(EARGF(usage()));

 		break;

 	}ARGEND