blob: 4f31c5fa056d907db491a8f661e5a44cf538ce28 [file] [log] [blame]
/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "SampleIterator"
//#define LOG_NDEBUG 0
#include <utils/Log.h>
#include "include/SampleIterator.h"
#include <arpa/inet.h>
#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/DataSource.h>
#include <media/stagefright/Utils.h>
#include "include/SampleTable.h"
namespace android {
SampleIterator::SampleIterator(SampleTable *table)
: mTable(table),
mInitialized(false),
mTimeToSampleIndex(0),
mTTSSampleIndex(0),
mTTSSampleTime(0),
mTTSCount(0),
mTTSDuration(0) {
reset();
}
void SampleIterator::reset() {
mSampleToChunkIndex = 0;
mFirstChunk = 0;
mFirstChunkSampleIndex = 0;
mStopChunk = 0;
mStopChunkSampleIndex = 0;
mSamplesPerChunk = 0;
mChunkDesc = 0;
}
status_t SampleIterator::seekTo(uint32_t sampleIndex) {
ALOGV("seekTo(%d)", sampleIndex);
if (sampleIndex >= mTable->mNumSampleSizes) {
return ERROR_END_OF_STREAM;
}
if (mTable->mSampleToChunkOffset < 0
|| mTable->mChunkOffsetOffset < 0
|| mTable->mSampleSizeOffset < 0
|| mTable->mTimeToSampleCount == 0) {
return ERROR_MALFORMED;
}
if (mInitialized && mCurrentSampleIndex == sampleIndex) {
return OK;
}
if (!mInitialized || sampleIndex < mFirstChunkSampleIndex) {
reset();
}
if (sampleIndex >= mStopChunkSampleIndex) {
status_t err;
if ((err = findChunkRange(sampleIndex)) != OK) {
ALOGE("findChunkRange failed");
return err;
}
}
CHECK(sampleIndex < mStopChunkSampleIndex);
if (mSamplesPerChunk == 0) {
ALOGE("b/22802344");
return ERROR_MALFORMED;
}
uint32_t chunk =
(sampleIndex - mFirstChunkSampleIndex) / mSamplesPerChunk
+ mFirstChunk;
if (!mInitialized || chunk != mCurrentChunkIndex) {
status_t err;
if ((err = getChunkOffset(chunk, &mCurrentChunkOffset)) != OK) {
ALOGE("getChunkOffset return error");
return err;
}
mCurrentChunkSampleSizes.clear();
uint32_t firstChunkSampleIndex =
mFirstChunkSampleIndex
+ mSamplesPerChunk * (chunk - mFirstChunk);
for (uint32_t i = 0; i < mSamplesPerChunk; ++i) {
size_t sampleSize;
if ((err = getSampleSizeDirect(
firstChunkSampleIndex + i, &sampleSize)) != OK) {
ALOGE("getSampleSizeDirect return error");
mCurrentChunkSampleSizes.clear();
return err;
}
mCurrentChunkSampleSizes.push(sampleSize);
}
mCurrentChunkIndex = chunk;
}
uint32_t chunkRelativeSampleIndex =
(sampleIndex - mFirstChunkSampleIndex) % mSamplesPerChunk;
mCurrentSampleOffset = mCurrentChunkOffset;
for (uint32_t i = 0; i < chunkRelativeSampleIndex; ++i) {
mCurrentSampleOffset += mCurrentChunkSampleSizes[i];
}
mCurrentSampleSize = mCurrentChunkSampleSizes[chunkRelativeSampleIndex];
if (sampleIndex < mTTSSampleIndex) {
mTimeToSampleIndex = 0;
mTTSSampleIndex = 0;
mTTSSampleTime = 0;
mTTSCount = 0;
mTTSDuration = 0;
}
status_t err;
if ((err = findSampleTimeAndDuration(
sampleIndex, &mCurrentSampleTime, &mCurrentSampleDuration)) != OK) {
ALOGE("findSampleTime return error");
return err;
}
mCurrentSampleIndex = sampleIndex;
mInitialized = true;
return OK;
}
status_t SampleIterator::findChunkRange(uint32_t sampleIndex) {
CHECK(sampleIndex >= mFirstChunkSampleIndex);
while (sampleIndex >= mStopChunkSampleIndex) {
if (mSampleToChunkIndex == mTable->mNumSampleToChunkOffsets) {
return ERROR_OUT_OF_RANGE;
}
mFirstChunkSampleIndex = mStopChunkSampleIndex;
const SampleTable::SampleToChunkEntry *entry =
&mTable->mSampleToChunkEntries[mSampleToChunkIndex];
mFirstChunk = entry->startChunk;
mSamplesPerChunk = entry->samplesPerChunk;
mChunkDesc = entry->chunkDesc;
if (mSampleToChunkIndex + 1 < mTable->mNumSampleToChunkOffsets) {
mStopChunk = entry[1].startChunk;
if (mStopChunk < mFirstChunk ||
(mStopChunk - mFirstChunk) > UINT32_MAX / mSamplesPerChunk ||
((mStopChunk - mFirstChunk) * mSamplesPerChunk >
UINT32_MAX - mFirstChunkSampleIndex)) {
return ERROR_OUT_OF_RANGE;
}
mStopChunkSampleIndex =
mFirstChunkSampleIndex
+ (mStopChunk - mFirstChunk) * mSamplesPerChunk;
} else {
mStopChunk = 0xffffffff;
mStopChunkSampleIndex = 0xffffffff;
}
++mSampleToChunkIndex;
}
return OK;
}
status_t SampleIterator::getChunkOffset(uint32_t chunk, off64_t *offset) {
*offset = 0;
if (chunk >= mTable->mNumChunkOffsets) {
return ERROR_OUT_OF_RANGE;
}
if (mTable->mChunkOffsetType == SampleTable::kChunkOffsetType32) {
uint32_t offset32;
if (mTable->mDataSource->readAt(
mTable->mChunkOffsetOffset + 8 + 4 * chunk,
&offset32,
sizeof(offset32)) < (ssize_t)sizeof(offset32)) {
return ERROR_IO;
}
*offset = ntohl(offset32);
} else {
CHECK_EQ(mTable->mChunkOffsetType, SampleTable::kChunkOffsetType64);
uint64_t offset64;
if (mTable->mDataSource->readAt(
mTable->mChunkOffsetOffset + 8 + 8 * chunk,
&offset64,
sizeof(offset64)) < (ssize_t)sizeof(offset64)) {
return ERROR_IO;
}
*offset = ntoh64(offset64);
}
return OK;
}
status_t SampleIterator::getSampleSizeDirect(
uint32_t sampleIndex, size_t *size) {
*size = 0;
if (sampleIndex >= mTable->mNumSampleSizes) {
return ERROR_OUT_OF_RANGE;
}
if (mTable->mDefaultSampleSize > 0) {
*size = mTable->mDefaultSampleSize;
return OK;
}
switch (mTable->mSampleSizeFieldSize) {
case 32:
{
if (mTable->mDataSource->readAt(
mTable->mSampleSizeOffset + 12 + 4 * sampleIndex,
size, sizeof(*size)) < (ssize_t)sizeof(*size)) {
return ERROR_IO;
}
*size = ntohl(*size);
break;
}
case 16:
{
uint16_t x;
if (mTable->mDataSource->readAt(
mTable->mSampleSizeOffset + 12 + 2 * sampleIndex,
&x, sizeof(x)) < (ssize_t)sizeof(x)) {
return ERROR_IO;
}
*size = ntohs(x);
break;
}
case 8:
{
uint8_t x;
if (mTable->mDataSource->readAt(
mTable->mSampleSizeOffset + 12 + sampleIndex,
&x, sizeof(x)) < (ssize_t)sizeof(x)) {
return ERROR_IO;
}
*size = x;
break;
}
default:
{
CHECK_EQ(mTable->mSampleSizeFieldSize, 4u);
uint8_t x;
if (mTable->mDataSource->readAt(
mTable->mSampleSizeOffset + 12 + sampleIndex / 2,
&x, sizeof(x)) < (ssize_t)sizeof(x)) {
return ERROR_IO;
}
*size = (sampleIndex & 1) ? x & 0x0f : x >> 4;
break;
}
}
return OK;
}
status_t SampleIterator::findSampleTimeAndDuration(
uint32_t sampleIndex, uint32_t *time, uint32_t *duration) {
if (sampleIndex >= mTable->mNumSampleSizes) {
return ERROR_OUT_OF_RANGE;
}
while (true) {
if (mTTSSampleIndex > UINT32_MAX - mTTSCount) {
return ERROR_OUT_OF_RANGE;
}
if(sampleIndex < mTTSSampleIndex + mTTSCount) {
break;
}
if (mTimeToSampleIndex == mTable->mTimeToSampleCount ||
(mTTSDuration != 0 && mTTSCount > UINT32_MAX / mTTSDuration) ||
mTTSSampleTime > UINT32_MAX - (mTTSCount * mTTSDuration)) {
return ERROR_OUT_OF_RANGE;
}
mTTSSampleIndex += mTTSCount;
mTTSSampleTime += mTTSCount * mTTSDuration;
mTTSCount = mTable->mTimeToSample[2 * mTimeToSampleIndex];
mTTSDuration = mTable->mTimeToSample[2 * mTimeToSampleIndex + 1];
++mTimeToSampleIndex;
}
*time = mTTSSampleTime + mTTSDuration * (sampleIndex - mTTSSampleIndex);
int32_t offset = mTable->getCompositionTimeOffset(sampleIndex);
if ((offset < 0 && *time < (offset == INT32_MIN ?
INT32_MAX : uint32_t(-offset))) ||
(offset > 0 && *time > UINT32_MAX - offset)) {
ALOGE("%u + %d would overflow", *time, offset);
return ERROR_OUT_OF_RANGE;
}
if (offset > 0) {
*time += offset;
} else {
*time -= (offset == INT32_MIN ? INT32_MAX : (-offset));
}
*duration = mTTSDuration;
return OK;
}
} // namespace android