mpv/libmpdemux/muxer_avi.c

669 lines
20 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <unistd.h>
#include <limits.h>
#include "config.h"
#include "../version.h"
#include "stream.h"
#include "demuxer.h"
#include "stheader.h"
#include "bswap.h"
#include "muxer.h"
#include "aviheader.h"
#include "ms_hdr.h"
#include "mp_msg.h"
extern char *info_name;
extern char *info_artist;
extern char *info_genre;
extern char *info_subject;
extern char *info_copyright;
extern char *info_sourceform;
extern char *info_comment;
/* #define ODML_CHUNKLEN 0x02000000 */ /* for testing purposes */
#define ODML_CHUNKLEN 0x40000000
#define ODML_NOTKEYFRAME 0x80000000U
#define MOVIALIGN 0x00001000
float avi_aspect_override = -1.0;
int write_odml = 1;
struct avi_odmlidx_entry {
uint64_t ofs;
uint32_t len;
uint32_t flags;
};
struct avi_odmlsuperidx_entry {
uint64_t ofs;
uint32_t len;
uint32_t duration;
};
struct avi_stream_info {
int idxsize;
int idxpos;
int superidxpos;
int superidxsize;
int riffofspos;
int riffofssize;
off_t *riffofs;
struct avi_odmlidx_entry *idx;
struct avi_odmlsuperidx_entry *superidx;
};
static unsigned int avi_aspect(muxer_stream_t *vstream)
{
int x,y;
float aspect = vstream->aspect;
if (avi_aspect_override > 0.0) {
aspect = avi_aspect_override;
}
if (aspect <= 0.0) return 0;
if (aspect > 15.99/9.0 && aspect < 16.01/9.0) {
return MAKE_AVI_ASPECT(16, 9);
}
if (aspect > 3.99/3.0 && aspect < 4.01/3.0) {
return MAKE_AVI_ASPECT(4, 3);
}
if (aspect >= 1.0) {
x = 16384;
y = (float)x / aspect;
} else {
y = 16384;
x = (float)y * aspect;
}
return MAKE_AVI_ASPECT(x, y);
}
static muxer_stream_t* avifile_new_stream(muxer_t *muxer,int type){
struct avi_stream_info *si;
muxer_stream_t* s;
if (!muxer) return NULL;
if(muxer->avih.dwStreams>=MUXER_MAX_STREAMS){
mp_msg(MSGT_MUXER, MSGL_ERR, "Too many streams! increase MUXER_MAX_STREAMS !\n");
return NULL;
}
s=malloc(sizeof(muxer_stream_t));
memset(s,0,sizeof(muxer_stream_t));
if(!s) return NULL; // no mem!?
muxer->streams[muxer->avih.dwStreams]=s;
s->type=type;
s->id=muxer->avih.dwStreams;
s->timer=0.0;
s->size=0;
s->muxer=muxer;
s->priv=si=malloc(sizeof(struct avi_stream_info));
memset(si,0,sizeof(struct avi_stream_info));
si->idxsize=256;
si->idx=malloc(sizeof(struct avi_odmlidx_entry)*si->idxsize);
si->riffofssize=16;
si->riffofs=malloc(sizeof(off_t)*(si->riffofssize+1));
memset(si->riffofs, 0, sizeof(off_t)*si->riffofssize);
switch(type){
case MUXER_TYPE_VIDEO:
s->ckid=mmioFOURCC(('0'+s->id/10),('0'+(s->id%10)),'d','c');
s->h.fccType=streamtypeVIDEO;
if(!muxer->def_v) muxer->def_v=s;
break;
case MUXER_TYPE_AUDIO:
s->ckid=mmioFOURCC(('0'+s->id/10),('0'+(s->id%10)),'w','b');
s->h.fccType=streamtypeAUDIO;
break;
default:
mp_msg(MSGT_MUXER, MSGL_WARN, "Warning! unknown stream type: %d\n",type);
return NULL;
}
muxer->avih.dwStreams++;
return s;
}
static void write_avi_chunk(FILE *f,unsigned int id,int len,void* data){
int le_len = le2me_32(len);
int le_id = le2me_32(id);
fwrite(&le_id,4,1,f);
fwrite(&le_len,4,1,f);
if(len>0){
if(data){
// DATA
fwrite(data,len,1,f);
if(len&1){ // padding
unsigned char zerobyte=0;
fwrite(&zerobyte,1,1,f);
}
} else {
// JUNK
char *avi_junk_data="[= MPlayer junk data! =]";
if(len&1) ++len; // padding
while(len>0){
int l=strlen(avi_junk_data);
if(l>len) l=len;
fwrite(avi_junk_data,l,1,f);
len-=l;
}
}
}
}
static void write_avi_list(FILE *f,unsigned int id,int len);
static void avifile_write_standard_index(muxer_t *muxer);
static void avifile_odml_new_riff(muxer_t *muxer)
{
struct avi_stream_info *vsi = muxer->def_v->priv;
FILE *f = muxer->file;
uint32_t riff[3];
mp_msg(MSGT_MUXER, MSGL_INFO, "ODML: Starting new RIFF chunk at %dMB.\n", (int)(muxer->file_end/1024/1024));
vsi->riffofspos++;
if (vsi->riffofspos>=vsi->riffofssize) {
vsi->riffofssize+=16;
vsi->riffofs=realloc(vsi->riffofs,sizeof(off_t)*(vsi->riffofssize+1));
}
vsi->riffofs[vsi->riffofspos] = ftello(f);
/* RIFF/AVIX chunk */
riff[0]=le2me_32(mmioFOURCC('R','I','F','F'));
riff[1]=0;
riff[2]=le2me_32(mmioFOURCC('A','V','I','X'));
fwrite(riff,12,1,f);
write_avi_list(f,listtypeAVIMOVIE,0);
muxer->file_end = ftello(f);
}
static void avifile_write_header(muxer_t *muxer);
static void avifile_write_chunk(muxer_stream_t *s,size_t len,unsigned int flags){
off_t rifflen;
muxer_t *muxer=s->muxer;
struct avi_stream_info *si = s->priv;
struct avi_stream_info *vsi = muxer->def_v->priv;
int paddedlen = len + (len&1);
if (s->type == MUXER_TYPE_VIDEO && !s->h.dwSuggestedBufferSize) {
off_t pos=ftell(muxer->file);
fseek(muxer->file, 0, SEEK_SET);
avifile_write_header(muxer);
fseek(muxer->file, pos, SEEK_SET);
}
rifflen = muxer->file_end - vsi->riffofs[vsi->riffofspos] - 8;
if (vsi->riffofspos == 0) {
rifflen += 8+muxer->idx_pos*sizeof(AVIINDEXENTRY);
}
if (rifflen + paddedlen > ODML_CHUNKLEN && write_odml == 1) {
if (vsi->riffofspos == 0) {
avifile_write_standard_index(muxer);
}
avifile_odml_new_riff(muxer);
}
if (vsi->riffofspos == 0) {
// add to the traditional index:
if(muxer->idx_pos>=muxer->idx_size){
muxer->idx_size+=256; // 4kB
muxer->idx=realloc(muxer->idx,16*muxer->idx_size);
}
muxer->idx[muxer->idx_pos].ckid=s->ckid;
muxer->idx[muxer->idx_pos].dwFlags=flags; // keyframe?
muxer->idx[muxer->idx_pos].dwChunkOffset=muxer->file_end-(muxer->movi_start-4);
muxer->idx[muxer->idx_pos].dwChunkLength=len;
++muxer->idx_pos;
}
// add to odml index
if(si->idxpos>=si->idxsize){
si->idxsize+=256;
si->idx=realloc(si->idx,sizeof(*si->idx)*si->idxsize);
}
si->idx[si->idxpos].flags=(flags&AVIIF_KEYFRAME)?0:ODML_NOTKEYFRAME;
si->idx[si->idxpos].ofs=muxer->file_end;
si->idx[si->idxpos].len=len;
++si->idxpos;
// write out the chunk:
write_avi_chunk(muxer->file,s->ckid,len,s->buffer); /* unsigned char */
// alter counters:
if (len > s->h.dwSuggestedBufferSize){
s->h.dwSuggestedBufferSize = len;
}
if(s->h.dwSampleSize){
// CBR
s->h.dwLength+=len/s->h.dwSampleSize;
if(len%s->h.dwSampleSize) mp_msg(MSGT_MUXER, MSGL_WARN, "Warning! len isn't divisable by samplesize!\n");
} else {
// VBR
s->h.dwLength++;
}
s->timer=(double)s->h.dwLength*s->h.dwScale/s->h.dwRate;
s->size+=len;
if((unsigned int)len>s->h.dwSuggestedBufferSize) s->h.dwSuggestedBufferSize=len;
muxer->file_end += 8 + paddedlen;
}
static void write_avi_list(FILE *f,unsigned int id,int len){
unsigned int list_id=FOURCC_LIST;
int le_len;
int le_id;
len+=4; // list fix
list_id = le2me_32(list_id);
le_len = le2me_32(len);
le_id = le2me_32(id);
fwrite(&list_id,4,1,f);
fwrite(&le_len,4,1,f);
fwrite(&le_id,4,1,f);
}
#define WFSIZE(wf) (sizeof(WAVEFORMATEX)+(wf)->cbSize)
static void avifile_write_header(muxer_t *muxer){
uint32_t riff[3];
unsigned int dmlh[1];
unsigned int i;
unsigned int hdrsize;
muxer_info_t info[16];
FILE *f = muxer->file;
VideoPropHeader vprp;
uint32_t aspect = avi_aspect(muxer->def_v);
off_t pos;
struct avi_stream_info *vsi = muxer->def_v->priv;
int isodml = vsi->riffofspos > 0;
if (aspect == 0) {
mp_msg(MSGT_MUXER, MSGL_INFO, "ODML: Aspect information not (yet?) available or unspecified, not writing vprp header.\n");
} else {
mp_msg(MSGT_MUXER, MSGL_INFO, "ODML: vprp aspect is %d:%d.\n", aspect >> 16, aspect & 0xffff);
}
if (isodml) {
unsigned int rifflen, movilen;
int i;
vsi->riffofs[vsi->riffofspos+1] = muxer->file_end;
/* fixup RIFF lengths */
for (i=0; i<=vsi->riffofspos; i++) {
rifflen = vsi->riffofs[i+1] - vsi->riffofs[i] - 8;
movilen = le2me_32(rifflen - 12);
rifflen = le2me_32(rifflen);
fseeko(f, vsi->riffofs[i]+4, SEEK_SET);
fwrite(&rifflen,4,1,f);
/* fixup movi length */
if (i > 0) {
fseeko(f, vsi->riffofs[i]+16, SEEK_SET);
fwrite(&movilen,4,1,f);
}
}
fseeko(f, 12, SEEK_SET);
} else {
// RIFF header:
riff[0]=mmioFOURCC('R','I','F','F');
riff[1]=muxer->file_end-2*sizeof(unsigned int); // filesize
riff[2]=formtypeAVI; // 'AVI '
riff[0]=le2me_32(riff[0]);
riff[1]=le2me_32(riff[1]);
riff[2]=le2me_32(riff[2]);
fwrite(&riff,12,1,f);
}
// update AVI header:
if(muxer->def_v){
int i;
muxer->avih.dwMicroSecPerFrame=1000000.0*muxer->def_v->h.dwScale/muxer->def_v->h.dwRate;
// muxer->avih.dwMaxBytesPerSec=1000000; // dummy!!!!! FIXME
// muxer->avih.dwPaddingGranularity=2; // ???
muxer->avih.dwFlags|=AVIF_ISINTERLEAVED|AVIF_TRUSTCKTYPE;
muxer->avih.dwTotalFrames=0;
for (i=0; i<muxer->idx_pos; i++) {
if (muxer->idx[i].ckid == muxer->def_v->ckid)
muxer->avih.dwTotalFrames++;
}
// muxer->avih.dwSuggestedBufferSize=muxer->def_v->h.dwSuggestedBufferSize;
muxer->avih.dwWidth=muxer->def_v->bih->biWidth;
muxer->avih.dwHeight=muxer->def_v->bih->biHeight;
}
// AVI header:
hdrsize=sizeof(muxer->avih)+8;
if (isodml) hdrsize+=sizeof(dmlh)+20; // dmlh
// calc total header size:
for(i=0;i<muxer->avih.dwStreams;i++){
muxer_stream_t *s = muxer->streams[i];
struct avi_stream_info *si = s->priv;
hdrsize+=12; // LIST
hdrsize+=sizeof(muxer->streams[i]->h)+8; // strh
switch(muxer->streams[i]->type){
case MUXER_TYPE_VIDEO:
hdrsize+=muxer->streams[i]->bih->biSize+8; // strf
if (aspect != 0) {
hdrsize+=8+4*(9+8*1); // vprp
}
break;
case MUXER_TYPE_AUDIO:
hdrsize+=WFSIZE(muxer->streams[i]->wf)+8; // strf
break;
}
if (isodml && si && si->superidx && si->superidxsize) {
hdrsize += 32 + 16*si->superidxsize; //indx
}
}
write_avi_list(f,listtypeAVIHEADER,hdrsize);
le2me_MainAVIHeader(&muxer->avih);
write_avi_chunk(f,ckidAVIMAINHDR,sizeof(muxer->avih),&muxer->avih); /* MainAVIHeader */
le2me_MainAVIHeader(&muxer->avih);
// stream headers:
for(i=0;i<muxer->avih.dwStreams;i++){
muxer_stream_t *s = muxer->streams[i];
struct avi_stream_info *si = s->priv;
unsigned int idxhdr[8];
int j,n;
hdrsize=sizeof(s->h)+8; // strh
if (si && si->superidx && si->superidxsize) {
hdrsize += 32 + 16*si->superidxsize; //indx
}
switch(s->type){
case MUXER_TYPE_VIDEO:
hdrsize+=s->bih->biSize+8; // strf
s->h.fccHandler = s->bih->biCompression;
s->h.rcFrame.right = s->bih->biWidth;
s->h.rcFrame.bottom = s->bih->biHeight;
if (aspect != 0) {
// fill out vprp info
memset(&vprp, 0, sizeof(vprp));
vprp.dwVerticalRefreshRate = (s->h.dwRate+s->h.dwScale-1)/s->h.dwScale;
vprp.dwHTotalInT = muxer->avih.dwWidth;
vprp.dwVTotalInLines = muxer->avih.dwHeight;
vprp.dwFrameAspectRatio = aspect;
vprp.dwFrameWidthInPixels = muxer->avih.dwWidth;
vprp.dwFrameHeightInLines = muxer->avih.dwHeight;
vprp.nbFieldPerFrame = 1;
vprp.FieldInfo[0].CompressedBMHeight = muxer->avih.dwHeight;
vprp.FieldInfo[0].CompressedBMWidth = muxer->avih.dwWidth;
vprp.FieldInfo[0].ValidBMHeight = muxer->avih.dwHeight;
vprp.FieldInfo[0].ValidBMWidth = muxer->avih.dwWidth;
hdrsize+=8+4*(9+8*1); // vprp
}
break;
case MUXER_TYPE_AUDIO:
hdrsize+=WFSIZE(s->wf)+8; // strf
s->h.fccHandler = s->wf->wFormatTag;
break;
}
write_avi_list(f,listtypeSTREAMHEADER,hdrsize);
le2me_AVIStreamHeader(&s->h);
write_avi_chunk(f,ckidSTREAMHEADER,sizeof(s->h),&s->h); /* AVISTreamHeader */ // strh
le2me_AVIStreamHeader(&s->h);
switch(s->type){
case MUXER_TYPE_VIDEO:
{
int biSize=s->bih->biSize;
le2me_BITMAPINFOHEADER(s->bih);
write_avi_chunk(f,ckidSTREAMFORMAT,biSize,s->bih); /* BITMAPINFOHEADER */
le2me_BITMAPINFOHEADER(s->bih);
if (aspect != 0) {
int fields = vprp.nbFieldPerFrame;
le2me_VideoPropHeader(&vprp);
le2me_VIDEO_FIELD_DESC(&vprp.FieldInfo[0]);
le2me_VIDEO_FIELD_DESC(&vprp.FieldInfo[1]);
write_avi_chunk(f,mmioFOURCC('v','p','r','p'),
sizeof(VideoPropHeader) -
sizeof(VIDEO_FIELD_DESC)*(2-fields),
&vprp); /* Video Properties Header */
}
}
break;
case MUXER_TYPE_AUDIO:
{
int wfsize = WFSIZE(s->wf);
le2me_WAVEFORMATEX(s->wf);
write_avi_chunk(f,ckidSTREAMFORMAT,wfsize,s->wf); /* WAVEFORMATEX */
le2me_WAVEFORMATEX(s->wf);
}
break;
}
if (isodml && si && si->superidx && si->superidxsize) {
n = si->superidxsize;
idxhdr[0] = le2me_32(mmioFOURCC('i', 'n', 'd', 'x'));
idxhdr[1] = le2me_32(24 + 16*n);
idxhdr[2] = le2me_32(0x00000004);
idxhdr[3] = le2me_32(si->superidxpos);
idxhdr[4] = le2me_32(s->ckid);
idxhdr[5] = 0;
idxhdr[6] = 0;
idxhdr[7] = 0;
fwrite(idxhdr,sizeof(idxhdr),1,f);
for (j=0; j<n; j++) {
struct avi_odmlsuperidx_entry *entry = &si->superidx[j];
unsigned int data[4];
data[0] = le2me_32(entry->ofs);
data[1] = le2me_32(entry->ofs >> 32);
data[2] = le2me_32(entry->len);
data[3] = le2me_32(entry->duration);
fwrite(data,sizeof(data),1,f);
}
}
}
// ODML
if (isodml) {
memset(dmlh, 0, sizeof(dmlh));
dmlh[0] = le2me_32(muxer->avih.dwTotalFrames);
write_avi_list(f,mmioFOURCC('o','d','m','l'),sizeof(dmlh)+8);
write_avi_chunk(f,mmioFOURCC('d','m','l','h'),sizeof(dmlh),dmlh);
}
// ============= INFO ===============
// always include software info
info[0].id=mmioFOURCC('I','S','F','T'); // Software:
info[0].text="MEncoder " VERSION;
// include any optional strings
i=1;
if(info_name!=NULL){
info[i].id=mmioFOURCC('I','N','A','M'); // Name:
info[i++].text=info_name;
}
if(info_artist!=NULL){
info[i].id=mmioFOURCC('I','A','R','T'); // Artist:
info[i++].text=info_artist;
}
if(info_genre!=NULL){
info[i].id=mmioFOURCC('I','G','N','R'); // Genre:
info[i++].text=info_genre;
}
if(info_subject!=NULL){
info[i].id=mmioFOURCC('I','S','B','J'); // Subject:
info[i++].text=info_subject;
}
if(info_copyright!=NULL){
info[i].id=mmioFOURCC('I','C','O','P'); // Copyright:
info[i++].text=info_copyright;
}
if(info_sourceform!=NULL){
info[i].id=mmioFOURCC('I','S','R','F'); // Source Form:
info[i++].text=info_sourceform;
}
if(info_comment!=NULL){
info[i].id=mmioFOURCC('I','C','M','T'); // Comment:
info[i++].text=info_comment;
}
info[i].id=0;
hdrsize=0;
// calc info size:
for(i=0;info[i].id!=0;i++) if(info[i].text){
size_t sz=strlen(info[i].text)+1;
hdrsize+=sz+8+sz%2;
}
// write infos:
if (hdrsize!=0){
write_avi_list(f,mmioFOURCC('I','N','F','O'),hdrsize);
for(i=0;info[i].id!=0;i++) if(info[i].text){
write_avi_chunk(f,info[i].id,strlen(info[i].text)+1,info[i].text);
}
}
// JUNK:
write_avi_chunk(f,ckidAVIPADDING,MOVIALIGN-(ftello(f)%MOVIALIGN)-8,NULL); /* junk */
if (!isodml) {
// 'movi' header:
write_avi_list(f,listtypeAVIMOVIE,muxer->movi_end-ftello(f)-12);
} else {
if (ftello(f) != MOVIALIGN) {
mp_msg(MSGT_MUXER, MSGL_ERR, "Opendml superindex is too big for reserved space!\n");
mp_msg(MSGT_MUXER, MSGL_ERR, "Expected filepos %d, real filepos %d, missing space %d\n", MOVIALIGN, ftell(muxer->file), ftell(muxer->file)-MOVIALIGN);
mp_msg(MSGT_MUXER, MSGL_ERR, "Try increasing MOVIALIGN in libmpdemux/muxer_avi.c\n");
}
write_avi_list(f,listtypeAVIMOVIE,muxer->movi_end-ftello(f)-12);
}
muxer->movi_start=ftello(muxer->file);
if (muxer->file_end == 0) muxer->file_end = ftello(muxer->file);
}
static void avifile_odml_write_index(muxer_t *muxer){
muxer_stream_t* s;
struct avi_stream_info *si;
int i;
for (i=0; i<muxer->avih.dwStreams; i++) {
int j,k,n,idxpos,len,last,entries_per_subidx;
unsigned int idxhdr[8];
s = muxer->streams[i];
si = s->priv;
/*
* According to Avery Lee MSMP wants the subidx chunks to have the same size.
*
* So this code figures out how many entries we can put into
* an ix?? chunk, so that each ix?? chunk has the same size and the offsets
* don't overflow (Using ODML_CHUNKLEN for that is a bit more restrictive
* than it has to be though).
*/
len = 0;
n = 0;
entries_per_subidx = INT_MAX;
do {
off_t start = si->idx[0].ofs;
last = entries_per_subidx;
for (j=0; j<si->idxpos; j++) {
len = si->idx[j].ofs - start;
if(len >= ODML_CHUNKLEN || n >= entries_per_subidx) {
if (entries_per_subidx > n) {
entries_per_subidx = n;
}
start = si->idx[j].ofs;
len = 0;
n = 0;
}
n++;
}
} while (last != entries_per_subidx);
si->superidxpos = (si->idxpos+entries_per_subidx-1) / entries_per_subidx;
mp_msg(MSGT_MUXER, MSGL_V, "ODML: Stream %d: Using %d entries per subidx, %d entries in superidx\n",
i, entries_per_subidx, si->superidxpos);
si->superidxsize = si->superidxpos;
si->superidx = malloc(sizeof(*si->superidx) * si->superidxsize);
memset(si->superidx, 0, sizeof(*si->superidx) * si->superidxsize);
idxpos = 0;
for (j=0; j<si->superidxpos; j++) {
off_t start = si->idx[idxpos].ofs;
int duration;
duration = 0;
for (k=0; k<entries_per_subidx && idxpos+k<si->idxpos; k++) {
duration += s->h.dwSampleSize ? si->idx[idxpos+k].len/s->h.dwSampleSize : 1;
}
idxhdr[0] = le2me_32((s->ckid << 16) | mmioFOURCC('i', 'x', 0, 0));
idxhdr[1] = le2me_32(24 + 8*k);
idxhdr[2] = le2me_32(0x01000002);
idxhdr[3] = le2me_32(k);
idxhdr[4] = le2me_32(s->ckid);
idxhdr[5] = le2me_32(start + 8);
idxhdr[6] = le2me_32((start + 8)>> 32);
idxhdr[7] = 0; /* unused */
si->superidx[j].len = 32 + 8*k;
si->superidx[j].ofs = ftello(muxer->file);
si->superidx[j].duration = duration;
fwrite(idxhdr,sizeof(idxhdr),1,muxer->file);
for (k=0; k<entries_per_subidx && idxpos<si->idxpos; k++) {
unsigned int entry[2];
entry[0] = le2me_32(si->idx[idxpos].ofs - start);
entry[1] = le2me_32(si->idx[idxpos].len | si->idx[idxpos].flags);
idxpos++;
fwrite(entry,sizeof(entry),1,muxer->file);
}
}
}
muxer->file_end=ftello(muxer->file);
}
static void avifile_write_standard_index(muxer_t *muxer){
muxer->movi_end=ftello(muxer->file);
if(muxer->idx && muxer->idx_pos>0){
int i;
// fixup index entries:
// for(i=0;i<muxer->idx_pos;i++) muxer->idx[i].dwChunkOffset-=muxer->movi_start-4;
// write index chunk:
for (i=0; i<muxer->idx_pos; i++) le2me_AVIINDEXENTRY((&muxer->idx[i]));
write_avi_chunk(muxer->file,ckidAVINEWINDEX,16*muxer->idx_pos,muxer->idx); /* AVIINDEXENTRY */
for (i=0; i<muxer->idx_pos; i++) le2me_AVIINDEXENTRY((&muxer->idx[i]));
muxer->avih.dwFlags|=AVIF_HASINDEX;
}
muxer->file_end=ftello(muxer->file);
}
static void avifile_write_index(muxer_t *muxer){
struct avi_stream_info *vsi = muxer->def_v->priv;
if (vsi->riffofspos > 0){
avifile_odml_write_index(muxer);
} else {
avifile_write_standard_index(muxer);
}
}
void muxer_init_muxer_avi(muxer_t *muxer){
muxer->cont_new_stream = &avifile_new_stream;
muxer->cont_write_chunk = &avifile_write_chunk;
muxer->cont_write_header = &avifile_write_header;
muxer->cont_write_index = &avifile_write_index;
}