track.c

一个用于智能手机的多媒体库适合S60 WinCE的跨平台开发库

/*
 *			GPAC - Multimedia Framework C SDK
 *
 *			Copyright (c) Jean Le Feuvre 2000-2005
 *					All rights reserved
 *
 *  This file is part of GPAC / ISO Media File Format sub-project
 *
 *  GPAC is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *   
 *  GPAC is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 *   
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 
 *
 */

#include <gpac/internal/isomedia_dev.h>

GF_TrackBox *GetTrackbyID(GF_MovieBox *moov, u32 TrackID)
{
	GF_TrackBox *trak;
	u32 i;
	if (!moov) return NULL;
	i=0;
	while ((trak = (GF_TrackBox *)gf_list_enum(moov->trackList, &i))) {
		if (trak->Header->trackID == TrackID) return trak;
	}
	return NULL;
}

GF_TrackBox *gf_isom_get_track(GF_MovieBox *moov, u32 trackNumber)
{
	GF_TrackBox *trak;
	if (!moov || !trackNumber || (trackNumber > gf_list_count(moov->trackList))) return NULL;
	trak = (GF_TrackBox*)gf_list_get(moov->trackList, trackNumber - 1);
	return trak;

}

//get the number of a track given its ID
//return 0 if not found error
u32 gf_isom_get_tracknum_from_id(GF_MovieBox *moov, u32 trackID)
{
	u32 i;
	GF_TrackBox *trak;
	i=0;
	while ((trak = (GF_TrackBox *)gf_list_enum(moov->trackList, &i))) {
		if (trak->Header->trackID == trackID) return i;
	}
	return 0;
}

//extraction of the ESD from the track
GF_Err GetESD(GF_MovieBox *moov, u32 trackID, u32 StreamDescIndex, GF_ESD **outESD)
{
	GF_Err e;
	GF_ESD *esd;
	GF_SampleTableBox *stbl;
	GF_TrackBox *trak, *OCRTrack;
	GF_TrackReferenceTypeBox *dpnd;
	GF_SLConfig *slc;
	GF_MPEGSampleEntryBox *entry;

	dpnd = NULL;
	*outESD = NULL;

	trak = gf_isom_get_track(moov, gf_isom_get_tracknum_from_id(moov, trackID));
	if (!trak) return GF_ISOM_INVALID_FILE;

	e = Media_GetESD(trak->Media, StreamDescIndex, &esd, 0);
	if (e) return e;

	e = Media_GetSampleDesc(trak->Media, StreamDescIndex, (GF_SampleEntryBox **) &entry, NULL);
	if (e) return e;
	//set the ID
	esd->ESID = trackID;
	
	//find stream dependencies
	e = Track_FindRef(trak, GF_ISOM_BOX_TYPE_DPND , &dpnd);
	if (e) return e;
	if (dpnd) {
		//ONLY ONE STREAM DEPENDENCY IS ALLOWED
		if (dpnd->trackIDCount != 1) return GF_ISOM_INVALID_MEDIA;
		//fix the spec: where is the index located ??
		esd->dependsOnESID = dpnd->trackIDs[0];
	} else {
		esd->dependsOnESID = 0;
	}

	//OK, get the OCR (in a REAL MP4File, OCR is 0 in ESD and is specified through track reference
	dpnd = NULL;
	OCRTrack = NULL;
	//find OCR dependencies
	e = Track_FindRef(trak, GF_ISOM_BOX_TYPE_SYNC, &dpnd);
	if (e) return e;
	if (dpnd) {
		if (dpnd->trackIDCount != 1) return GF_ISOM_INVALID_MEDIA;
		esd->OCRESID = dpnd->trackIDs[0];
		OCRTrack = gf_isom_get_track_from_id(trak->moov, dpnd->trackIDs[0]);

		while (OCRTrack) {
			/*if we have a dependency on a track that doesn't have OCR dep, remove that dependency*/
			e = Track_FindRef(OCRTrack, GF_ISOM_BOX_TYPE_SYNC, &dpnd);
			if (e || !dpnd || !dpnd->trackIDCount) {
				OCRTrack = NULL;
				goto default_sync;
			}
			/*this is explicit desync*/
			if (dpnd && ((dpnd->trackIDs[0]==0) || (dpnd->trackIDs[0]==OCRTrack->Header->trackID))) break;
			/*loop in OCRs, break it*/
			if (esd->ESID == OCRTrack->Header->trackID) {
				OCRTrack = NULL;
				goto default_sync;
			}
			/*check next*/
			OCRTrack = gf_isom_get_track_from_id(trak->moov, dpnd->trackIDs[0]);
		}
		if (!OCRTrack) goto default_sync;
	} else {
default_sync:
		/*all tracks are sync'ed by default*/
		if (trak->moov->mov->es_id_default_sync<0) {
			if (esd->OCRESID)
				trak->moov->mov->es_id_default_sync = esd->OCRESID;
			else
				trak->moov->mov->es_id_default_sync = esd->ESID;
		}
		if (trak->moov->mov->es_id_default_sync) esd->OCRESID = (u16) trak->moov->mov->es_id_default_sync;
		/*cf ESD writer*/
		if (esd->OCRESID == esd->ESID) esd->OCRESID = 0;
	}



	//update the IPI stuff if needed
	if (esd->ipiPtr != NULL) {
		dpnd = NULL;
		e = Track_FindRef(trak, GF_ISOM_BOX_TYPE_IPIR, &dpnd);
		if (e) return e;
		if (dpnd) {
			if (esd->ipiPtr->tag != GF_ODF_ISOM_IPI_PTR_TAG) return GF_ISOM_INVALID_FILE;
			//OK, retrieve the ID: the IPI_ES_Id is currently the ref track
			esd->ipiPtr->IPI_ES_Id = dpnd->trackIDs[esd->ipiPtr->IPI_ES_Id - 1];
			//and change the tag
			esd->ipiPtr->tag = GF_ODF_IPI_PTR_TAG;
		} else {
			return GF_ISOM_INVALID_FILE;
		}
	}

	if ((trak->Media->mediaHeader->packedLanguage[0] != 'u')
		|| (trak->Media->mediaHeader->packedLanguage[1] != 'n')
		|| (trak->Media->mediaHeader->packedLanguage[2] != 'd') ) {
		if (!esd->langDesc) esd->langDesc = (GF_Language *) gf_odf_desc_new(GF_ODF_LANG_TAG);

		esd->langDesc->langCode = trak->Media->mediaHeader->packedLanguage[0]; esd->langDesc->langCode <<= 8;
		esd->langDesc->langCode |= trak->Media->mediaHeader->packedLanguage[1]; esd->langDesc->langCode <<= 8;
		esd->langDesc->langCode |= trak->Media->mediaHeader->packedLanguage[2];
	}

	/*normally all files shall be stored with predefined=SLPredef_MP4, but of course some are broken (philips)
	so we just check the ESD_URL. If set, use the given cfg, otherwise always rewrite it*/
	if (esd->URLString != NULL) {
		*outESD = esd;
		return GF_OK;
	}

	//if we are in publishing mode and we have an SLConfig specified, use it as is
	switch (entry->type) {
	case GF_ISOM_BOX_TYPE_MP4V:
		slc = ((GF_MPEGVisualSampleEntryBox *)entry)->slc;
		break;
	case GF_ISOM_BOX_TYPE_MP4A:
		slc = ((GF_MPEGAudioSampleEntryBox *)entry)->slc;
		break;
	case GF_ISOM_BOX_TYPE_MP4S:
		slc = entry->slc;
		break;
	default:
		slc = NULL;
		break;
	}
	if (slc) {
		gf_odf_desc_del((GF_Descriptor *)esd->slConfig);
		gf_odf_desc_copy((GF_Descriptor *)slc, (GF_Descriptor **)&esd->slConfig);
		*outESD = esd;
		return GF_OK;
	}
	//otherwise use the regular mapping
	
	//this is a desc for a media in the file, let's rewrite some param
	esd->slConfig->timestampLength = 32;
	esd->slConfig->timestampResolution = trak->Media->mediaHeader->timeScale;
	//NO OCR from MP4File streams (eg, constant OC Res one)
	esd->slConfig->OCRLength = 0;
	if (OCRTrack) {
		esd->slConfig->OCRResolution = OCRTrack->Media->mediaHeader->timeScale;
	} else {
		esd->slConfig->OCRResolution = 0;
	}
	stbl = trak->Media->information->sampleTable;
	// a little optimization here: if all our samples are sync, 
	//set the RAPOnly to true... for external users...
	if (! stbl->SyncSample) {
		esd->slConfig->hasRandomAccessUnitsOnlyFlag = 1;
		esd->slConfig->useRandomAccessPointFlag = 0;
	} else {
		esd->slConfig->hasRandomAccessUnitsOnlyFlag = 0;
		//signal we are NOT using sync points if no info is present in the table
		esd->slConfig->useRandomAccessPointFlag = stbl->SyncSample->entryCount ? 1 : 0;
	}
	//do we have DegradationPriority ?
	if (stbl->DegradationPriority) {
		esd->slConfig->degradationPriorityLength = 15;
	} else {
		esd->slConfig->degradationPriorityLength = 0;
	}
	//paddingBits
	if (stbl->PaddingBits) {
		esd->slConfig->usePaddingFlag = 1;
	}
	//change to support reflecting OD streams
	esd->slConfig->useAccessUnitEndFlag = 1;
	esd->slConfig->useAccessUnitStartFlag = 1;

	//signal we do have padding flag (since we only use logical SL packet
	//the user can decide whether to use the info or not
	esd->slConfig->usePaddingFlag = stbl->PaddingBits ? 1 : 0;

	//same with degradation priority
	esd->slConfig->degradationPriorityLength = stbl->DegradationPriority ? 32 : 0;

	//this new SL will be OUT OF THE FILE. Let's set its predefined to 0
	esd->slConfig->predefined = 0;
	
	*outESD = esd;
	return GF_OK;
}


//extraction of the ESD from the track for the given time
GF_Err GetESDForTime(GF_MovieBox *moov, u32 trackID, u64 CTS, GF_ESD **outESD)
{
	GF_Err e;
	u32 sampleDescIndex;
	GF_TrackBox *trak;

	trak = gf_isom_get_track(moov, gf_isom_get_tracknum_from_id(moov, trackID));
	if (!trak) return GF_ISOM_INVALID_FILE;
	
	e = Media_GetSampleDescIndex(trak->Media, CTS, &sampleDescIndex );
	if (e) return e;
	return GetESD(moov, trackID, sampleDescIndex, outESD);
}


GF_Err Track_FindRef(GF_TrackBox *trak, u32 ReferenceType, GF_TrackReferenceTypeBox **dpnd)
{
	GF_TrackReferenceBox *ref;
	GF_Box *a;
	u32 i;
	if (! trak) return GF_BAD_PARAM;
	if (! trak->References) {
		*dpnd = NULL;
		return GF_OK;
	}
	ref = trak->References;
	i=0;
	while ((a = (GF_Box *)gf_list_enum(ref->boxList, &i))) {
		if (a->type == ReferenceType) {
			*dpnd = (GF_TrackReferenceTypeBox *)a;
			return GF_OK;
		}
	}
	*dpnd = NULL;
	return GF_OK;	
}

Bool Track_IsMPEG4Stream(u32 HandlerType)
{
	switch (HandlerType) {
	case GF_ISOM_MEDIA_VISUAL:
	case GF_ISOM_MEDIA_AUDIO:
    case GF_ISOM_MEDIA_SUBPIC:
	case GF_ISOM_MEDIA_OD:
	case GF_ISOM_MEDIA_OCR:
	case GF_ISOM_MEDIA_SCENE:
	case GF_ISOM_MEDIA_MPEG7:
	case GF_ISOM_MEDIA_OCI:
	case GF_ISOM_MEDIA_IPMP:
	case GF_ISOM_MEDIA_MPEGJ:
	case GF_ISOM_MEDIA_ESM:
		return 1;
	/*Timedtext is NOT an MPEG-4 stream*/
	default:
		return 0;
	}
}


GF_Err SetTrackDuration(GF_TrackBox *trak)
{
	u64 trackDuration;
	u32 i;
	GF_EdtsEntry *ent;
	GF_EditListBox *elst;
	GF_Err e;

	//the total duration is the media duration: adjust it in case...
	e = Media_SetDuration(trak);
	if (e) return e;

	//if we have an edit list, the duration is the sum of all the editList 
	//entries' duration (always expressed in MovieTimeScale)
	if (trak->editBox && trak->editBox->editList) {
		trackDuration = 0;
		elst = trak->editBox->editList;
		i=0;
		while ((ent = (GF_EdtsEntry*)gf_list_enum(elst->entryList, &i))) {
			trackDuration += ent->segmentDuration;
		}
	} else {
		//assert the timeScales are non-NULL
		if (!trak->moov->mvhd->timeScale && !trak->Media->mediaHeader->timeScale) return GF_ISOM_INVALID_FILE;
		trackDuration = (trak->Media->mediaHeader->duration * trak->moov->mvhd->timeScale) / trak->Media->mediaHeader->timeScale;
	}
	trak->Header->duration = trackDuration;
	trak->Header->modificationTime = gf_isom_get_mp4time();
	return GF_OK;
}


#ifndef	GF_ISOM_NO_FRAGMENTS

GF_Err MergeTrack(GF_TrackBox *trak, GF_TrackFragmentBox *traf, u64 *moof_offset)
{
	u32 i, j, chunk_size;
	u64 base_offset, data_offset;
	u32 def_duration, DescIndex, def_size, def_flags;
	u32 duration, size, flags, cts_offset;
	u8 pad, sync;
	u16 degr;
	GF_TrackFragmentRunBox *trun;
	GF_TrunEntry *ent;

	void stbl_AppendTime(GF_SampleTableBox *stbl, u32 duration);
	void stbl_AppendSize(GF_SampleTableBox *stbl, u32 size);
	void stbl_AppendChunk(GF_SampleTableBox *stbl, u64 offset);
	void stbl_AppendSampleToChunk(GF_SampleTableBox *stbl, u32 DescIndex, u32 samplesInChunk);
	void stbl_AppendCTSOffset(GF_SampleTableBox *stbl, u32 CTSOffset);
	void stbl_AppendRAP(GF_SampleTableBox *stbl, u8 isRap);
	void stbl_AppendPadding(GF_SampleTableBox *stbl, u8 padding);
	void stbl_AppendDegradation(GF_SampleTableBox *stbl, u16 DegradationPriority);


	//setup all our defaults
	DescIndex = (traf->tfhd->flags & GF_ISOM_TRAF_SAMPLE_DESC) ? traf->tfhd->sample_desc_index : traf->trex->def_sample_desc_index;
	def_duration = (traf->tfhd->flags & GF_ISOM_TRAF_SAMPLE_DUR) ? traf->tfhd->def_sample_duration : traf->trex->def_sample_duration;
	def_size = (traf->tfhd->flags & GF_ISOM_TRAF_SAMPLE_SIZE) ? traf->tfhd->def_sample_size : traf->trex->def_sample_size;
	def_flags = (traf->tfhd->flags & GF_ISOM_TRAF_SAMPLE_FLAGS) ? traf->tfhd->def_sample_flags : traf->trex->def_sample_flags;

	//locate base offset
	base_offset = (traf->tfhd->flags & GF_ISOM_TRAF_BASE_OFFSET) ? traf->tfhd->base_data_offset : *moof_offset;

	chunk_size = 0;

	i=0;
	while ((trun = (GF_TrackFragmentRunBox *)gf_list_enum(traf->TrackRuns, &i))) {
		//merge the run
		for (j=0;j<trun->sample_count; j++) {
			ent = (GF_TrunEntry*)gf_list_get(trun->entries, j);
			size = def_size;
			duration = def_duration;
			flags = def_flags;
			
			if (ent) {
				if (trun->flags & GF_ISOM_TRUN_DURATION) duration = ent->Duration;
				if (trun->flags & GF_ISOM_TRUN_SIZE) size = ent->size;
				if (trun->flags & GF_ISOM_TRUN_FLAGS) {
					flags = ent->flags;
				} else if (!j && (trun->flags & GF_ISOM_TRUN_FIRST_FLAG)) {
					flags = trun->first_sample_flags;