Add H262 support for TS.

Built on top of https://github.com/google/ExoPlayer/pull/915.
This commit is contained in:
Oliver Woodman 2015-11-17 16:01:28 +00:00
parent b1e4283058
commit 8234a25110
2 changed files with 240 additions and 0 deletions

View file

@ -0,0 +1,236 @@
/*
* Copyright (C) 2014 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.
*/
package com.google.android.exoplayer.extractor.ts;
import com.google.android.exoplayer.C;
import com.google.android.exoplayer.MediaFormat;
import com.google.android.exoplayer.extractor.TrackOutput;
import com.google.android.exoplayer.util.MimeTypes;
import com.google.android.exoplayer.util.NalUnitUtil;
import com.google.android.exoplayer.util.ParsableByteArray;
import java.util.Arrays;
import java.util.Collections;
/**
* Parses a continuous H262 byte stream and extracts individual frames.
*/
/* package */ final class H262Reader extends ElementaryStreamReader {
private static final int START_PICTURE = 0x00;
private static final int START_SEQUENCE_HEADER = 0xB3;
private static final int START_EXTENSION = 0xB5;
private static final int START_GROUP = 0xB8;
// State that should not be reset on seek.
private boolean hasOutputFormat;
// State that should be reset on seek.
private final boolean[] prefixFlags;
private final CsdBuffer csdBuffer;
private boolean foundFirstFrameInGroup;
private long totalBytesWritten;
// Per sample state that gets reset at the start of each frame.
private boolean isKeyframe;
private long framePosition;
private long frameTimeUs;
public H262Reader(TrackOutput output) {
super(output);
prefixFlags = new boolean[4];
csdBuffer = new CsdBuffer(128);
}
@Override
public void seek() {
NalUnitUtil.clearPrefixFlags(prefixFlags);
csdBuffer.reset();
foundFirstFrameInGroup = false;
totalBytesWritten = 0;
}
@Override
public void consume(ParsableByteArray data, long pesTimeUs, boolean startOfPacket) {
while (data.bytesLeft() > 0) {
int offset = data.getPosition();
int limit = data.limit();
byte[] dataArray = data.data;
// Append the data to the buffer.
totalBytesWritten += data.bytesLeft();
output.sampleData(data, data.bytesLeft());
int searchOffset = offset;
while (true) {
int startCodeOffset = NalUnitUtil.findNalUnit(dataArray, searchOffset, limit, prefixFlags);
if (startCodeOffset == limit) {
// We've scanned to the end of the data without finding another start code.
if (!hasOutputFormat) {
csdBuffer.onData(dataArray, offset, limit);
}
return;
}
// We've found a start code with the following value.
int startCodeValue = data.data[startCodeOffset + 3] & 0xFF;
if (!hasOutputFormat) {
// This is the number of bytes from the current offset to the start of the next start
// code. It may be negative if the start code started in the previously consumed data.
int lengthToStartCode = startCodeOffset - offset;
if (lengthToStartCode > 0) {
csdBuffer.onData(dataArray, offset, startCodeOffset);
}
// This is the number of bytes belonging to the next start code that have already been
// passed to csdDataTargetBuffer.
int bytesAlreadyPassed = lengthToStartCode < 0 ? -lengthToStartCode : 0;
if (csdBuffer.onStartCode(startCodeValue, bytesAlreadyPassed)) {
// The csd data is complete, so we can parse and output the media format.
output.format(parseMediaFormat(csdBuffer));
hasOutputFormat = true;
}
}
if (hasOutputFormat && (startCodeValue == START_GROUP || startCodeValue == START_PICTURE)) {
int bytesWrittenPastStartCode = limit - startCodeOffset;
if (foundFirstFrameInGroup) {
int flags = isKeyframe ? C.SAMPLE_FLAG_SYNC : 0;
int size = (int) (totalBytesWritten - framePosition) - bytesWrittenPastStartCode;
output.sampleMetadata(frameTimeUs, flags, size, bytesWrittenPastStartCode, null);
isKeyframe = false;
}
if (startCodeValue == START_GROUP) {
foundFirstFrameInGroup = false;
isKeyframe = true;
} else /* startCode == START_PICTURE */ {
foundFirstFrameInGroup = true;
frameTimeUs = pesTimeUs;
framePosition = totalBytesWritten - bytesWrittenPastStartCode;
}
}
offset = startCodeOffset;
searchOffset = offset + 3;
}
}
}
@Override
public void packetFinished() {
// Do nothing.
}
private static MediaFormat parseMediaFormat(CsdBuffer csdBuffer) {
byte[] csdData = Arrays.copyOf(csdBuffer.data, csdBuffer.length);
int firstByte = csdData[4] & 0xFF;
int secondByte = csdData[5] & 0xFF;
int thirdByte = csdData[6] & 0xFF;
int width = (firstByte << 4) | (secondByte >> 4);
int height = (secondByte & 0x0F) << 8 | thirdByte;
float pixelWidthHeightRatio = 1f;
int aspectRatioCode = (csdData[7] & 0xF0) >> 4;
switch(aspectRatioCode) {
case 2:
pixelWidthHeightRatio = (3 * width) / (float) (4 * height);
break;
case 3:
pixelWidthHeightRatio = (9 * width) / (float) (16 * height);
break;
case 4:
pixelWidthHeightRatio = (100 * width) / (float) (121 * height);
break;
default:
// Do nothing.
break;
}
return MediaFormat.createVideoFormat(null, MimeTypes.VIDEO_MPEG2, MediaFormat.NO_VALUE,
MediaFormat.NO_VALUE, C.UNKNOWN_TIME_US, width, height, Collections.singletonList(csdData),
MediaFormat.NO_VALUE, pixelWidthHeightRatio);
}
private static final class CsdBuffer {
private boolean isFilling;
private boolean seenExtensionStartCode;
public int length;
public byte[] data;
public CsdBuffer(int initialCapacity) {
data = new byte[initialCapacity];
}
/**
* Resets the buffer, clearing any data that it holds.
*/
public void reset() {
isFilling = false;
seenExtensionStartCode = false;
length = 0;
}
/**
* Invoked when a start code is encountered in the stream.
*
* @param startCodeValue The start code value.
* @param bytesAlreadyPassed The number of bytes of the start code that have already been
* passed to {@link #onData(byte[], int, int)}, or 0.
* @return True if the csd data is now complete. False otherwise. If true is returned, neither
* this method or {@link #onData(byte[], int, int)} should be called again without an
* interleaving call to {@link #reset()}.
*/
public boolean onStartCode(int startCodeValue, int bytesAlreadyPassed) {
if (isFilling) {
if (!seenExtensionStartCode && startCodeValue == START_EXTENSION) {
seenExtensionStartCode = true;
} else {
length -= bytesAlreadyPassed;
isFilling = false;
return true;
}
} else if (startCodeValue == START_SEQUENCE_HEADER) {
isFilling = true;
}
return false;
}
/**
* Invoked to pass stream data.
*
* @param newData Holds the data being passed.
* @param offset The offset of the data in {@code data}.
* @param limit The limit (exclusive) of the data in {@code data}.
*/
public void onData(byte[] newData, int offset, int limit) {
if (!isFilling) {
return;
}
int readLength = limit - offset;
if (data.length < length + readLength) {
data = Arrays.copyOf(data, (length + readLength) * 2);
}
System.arraycopy(newData, offset, data, length, readLength);
length += readLength;
}
}
}

View file

@ -46,6 +46,7 @@ public final class TsExtractor implements Extractor {
private static final int TS_STREAM_TYPE_AAC = 0x0F;
private static final int TS_STREAM_TYPE_AC3 = 0x81;
private static final int TS_STREAM_TYPE_E_AC3 = 0x87;
private static final int TS_STREAM_TYPE_H262 = 0x02;
private static final int TS_STREAM_TYPE_H264 = 0x1B;
private static final int TS_STREAM_TYPE_H265 = 0x24;
private static final int TS_STREAM_TYPE_ID3 = 0x15;
@ -313,6 +314,9 @@ public final class TsExtractor implements Extractor {
case TS_STREAM_TYPE_AC3:
pesPayloadReader = new Ac3Reader(output.track(streamType));
break;
case TS_STREAM_TYPE_H262:
pesPayloadReader = new H262Reader(output.track(TS_STREAM_TYPE_H262));
break;
case TS_STREAM_TYPE_H264:
pesPayloadReader = new H264Reader(output.track(TS_STREAM_TYPE_H264),
new SeiReader(output.track(TS_STREAM_TYPE_EIA608)), idrKeyframesOnly);