MediaCodec is generally used like this: *
* MediaCodec codec = MediaCodec.createDecoderByType(type);
* codec.configure(format, ...);
* codec.start();
* ByteBuffer[] inputBuffers = codec.getInputBuffers();
* ByteBuffer[] outputBuffers = codec.getOutputBuffers();
* for (;;) {
* int inputBufferIndex = codec.dequeueInputBuffer(timeoutUs);
* if (inputBufferIndex >= 0) {
* // fill inputBuffers[inputBufferIndex] with valid data
* ...
* codec.queueInputBuffer(inputBufferIndex, ...);
* }
*
* int outputBufferIndex = codec.dequeueOutputBuffer(timeoutUs);
* if (outputBufferIndex >= 0) {
* // outputBuffer is ready to be processed or rendered.
* ...
* codec.releaseOutputBuffer(outputBufferIndex, ...);
* } else if (outputBufferIndex == MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED) {
* outputBuffers = codec.getOutputBuffers();
* } else if (outputBufferIndex == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
* // Subsequent data will conform to new format.
* MediaFormat format = codec.getOutputFormat();
* ...
* }
* }
* codec.stop();
* codec.release();
* codec = null;
*
*
* Each codec maintains a number of input and output buffers that are
* referred to by index in API calls.
* The contents of these buffers is represented by the ByteBuffer[] arrays
* accessible through getInputBuffers() and getOutputBuffers().
*
* After a successful call to {@link #start} the client "owns" neither
* input nor output buffers, subsequent calls to {@link #dequeueInputBuffer}
* and {@link #dequeueOutputBuffer} then transfer ownership from the codec
* to the client.* The client is not required to resubmit/release buffers immediately * to the codec, the sample code above simply does this for simplicity's sake.
* Once the client has an input buffer available it can fill it with data * and submit it it to the codec via a call to {@link #queueInputBuffer}.
* The codec in turn will return an output buffer to the client in response * to {@link #dequeueOutputBuffer}. After the output buffer has been processed * a call to {@link #releaseOutputBuffer} will return it to the codec. * If a video surface has been provided in the call to {@link #configure}, * {@link #releaseOutputBuffer} optionally allows rendering of the buffer * to the surface.
* * Input buffers (for decoders) and Output buffers (for encoders) contain * encoded data according to the format's type. For video types this data * is all the encoded data representing a single moment in time, for audio * data this is slightly relaxed in that a buffer may contain multiple * encoded frames of audio. In either case, buffers do not start and end on * arbitrary byte boundaries, this is not a stream of bytes, it's a stream * of access units.
* * Most formats also require the actual data to be prefixed by a number * of buffers containing setup data, or codec specific data, i.e. the * first few buffers submitted to the codec object after starting it must * be codec specific data marked as such using the flag {@link #BUFFER_FLAG_CODEC_CONFIG} * in a call to {@link #queueInputBuffer}. * * Codec specific data included in the format passed to {@link #configure} * (in ByteBuffer entries with keys "csd-0", "csd-1", ...) is automatically * submitted to the codec, this data MUST NOT be submitted explicitly by the * client. * * Once the client reaches the end of the input data it signals the end of * the input stream by specifying a flag of {@link #BUFFER_FLAG_END_OF_STREAM} in the call to * {@link #queueInputBuffer}. The codec will continue to return output buffers * until it eventually signals the end of the output stream by specifying * the same flag ({@link #BUFFER_FLAG_END_OF_STREAM}) on the BufferInfo returned in * {@link #dequeueOutputBuffer}. * * In order to start decoding data that's not adjacent to previously submitted * data (i.e. after a seek) it is necessary to {@link #flush} the decoder. * Any input or output buffers the client may own at the point of the flush are * immediately revoked, i.e. after a call to {@link #flush} the client does not * own any buffers anymore. * Note that the format of the data submitted after a flush must not change, * flush does not support format discontinuities, * for this a full stop(), configure(), start() cycle is necessary. * */ final public class MediaCodec { /** * Per buffer metadata includes an offset and size specifying * the range of valid data in the associated codec buffer. */ public final static class BufferInfo { public void set( int newOffset, int newSize, long newTimeUs, int newFlags) { offset = newOffset; size = newSize; presentationTimeUs = newTimeUs; flags = newFlags; } public int offset; public int size; public long presentationTimeUs; public int flags; }; // The follow flag constants MUST stay in sync with their equivalents // in MediaCodec.h ! /** * This indicates that the buffer marked as such contains the data * for a sync frame. */ public static final int BUFFER_FLAG_SYNC_FRAME = 1; /** * This indicated that the buffer marked as such contains codec * initialization / codec specific data instead of media data. */ public static final int BUFFER_FLAG_CODEC_CONFIG = 2; /** * This signals the end of stream, i.e. no buffers will be available * after this, unless of course, {@link #flush} follows. */ public static final int BUFFER_FLAG_END_OF_STREAM = 4; /** * Instantiate a decoder supporting input data of the given mime type. * * The following is a partial list of defined mime types and their semantics: *
* The application is responsible for calling release() on the Surface when
* done.
*/
public native final Surface createInputSurface();
/**
* After successfully configuring the component, call start. On return
* you can query the component for its input/output buffers.
*/
public native final void start();
/**
* Finish the decode/encode session, note that the codec instance
* remains active and ready to be {@link #start}ed again.
* To ensure that it is available to other client call {@link #release}
* and don't just rely on garbage collection to eventually do this for you.
*/
public native final void stop();
/**
* Flush both input and output ports of the component, all indices
* previously returned in calls to {@link #dequeueInputBuffer} and
* {@link #dequeueOutputBuffer} become invalid.
*/
public native final void flush();
public final static class CryptoException extends RuntimeException {
public CryptoException(int errorCode, String detailMessage) {
super(detailMessage);
mErrorCode = errorCode;
}
public int getErrorCode() {
return mErrorCode;
}
private int mErrorCode;
}
/**
* After filling a range of the input buffer at the specified index
* submit it to the component.
*
* Many decoders require the actual compressed data stream to be
* preceded by "codec specific data", i.e. setup data used to initialize
* the codec such as PPS/SPS in the case of AVC video or code tables
* in the case of vorbis audio.
* The class {@link android.media.MediaExtractor} provides codec
* specific data as part of
* the returned track format in entries named "csd-0", "csd-1" ...
*
* These buffers should be submitted using the flag {@link #BUFFER_FLAG_CODEC_CONFIG}.
*
* To indicate that this is the final piece of input data (or rather that
* no more input data follows unless the decoder is subsequently flushed)
* specify the flag {@link #BUFFER_FLAG_END_OF_STREAM}.
*
* @param index The index of a client-owned input buffer previously returned
* in a call to {@link #dequeueInputBuffer}.
* @param offset The byte offset into the input buffer at which the data starts.
* @param size The number of bytes of valid input data.
* @param presentationTimeUs The time at which this buffer should be rendered.
* @param flags A bitmask of flags {@link #BUFFER_FLAG_SYNC_FRAME},
* {@link #BUFFER_FLAG_CODEC_CONFIG} or {@link #BUFFER_FLAG_END_OF_STREAM}.
* @throws CryptoException if a crypto object has been specified in
* {@link #configure}
*/
public native final void queueInputBuffer(
int index,
int offset, int size, long presentationTimeUs, int flags)
throws CryptoException;
// The following mode constants MUST stay in sync with their equivalents
// in media/hardware/CryptoAPI.h !
public static final int CRYPTO_MODE_UNENCRYPTED = 0;
public static final int CRYPTO_MODE_AES_CTR = 1;
/**
* Metadata describing the structure of a (at least partially) encrypted
* input sample.
* A buffer's data is considered to be partitioned into "subSamples",
* each subSample starts with a (potentially empty) run of plain,
* unencrypted bytes followed by a (also potentially empty) run of
* encrypted bytes.
* numBytesOfClearData can be null to indicate that all data is encrypted.
* This information encapsulates per-sample metadata as outlined in
* ISO/IEC FDIS 23001-7:2011 "Common encryption in ISO base media file format files".
*/
public final static class CryptoInfo {
public void set(
int newNumSubSamples,
int[] newNumBytesOfClearData,
int[] newNumBytesOfEncryptedData,
byte[] newKey,
byte[] newIV,
int newMode) {
numSubSamples = newNumSubSamples;
numBytesOfClearData = newNumBytesOfClearData;
numBytesOfEncryptedData = newNumBytesOfEncryptedData;
key = newKey;
iv = newIV;
mode = newMode;
}
/**
* The number of subSamples that make up the buffer's contents.
*/
public int numSubSamples;
/**
* The number of leading unencrypted bytes in each subSample.
*/
public int[] numBytesOfClearData;
/**
* The number of trailing encrypted bytes in each subSample.
*/
public int[] numBytesOfEncryptedData;
/**
* A 16-byte opaque key
*/
public byte[] key;
/**
* A 16-byte initialization vector
*/
public byte[] iv;
/**
* The type of encryption that has been applied,
* see {@link #CRYPTO_MODE_UNENCRYPTED} and {@link #CRYPTO_MODE_AES_CTR}.
*/
public int mode;
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append(numSubSamples + " subsamples, key [");
String hexdigits = "0123456789abcdef";
for (int i = 0; i < key.length; i++) {
builder.append(hexdigits.charAt((key[i] & 0xf0) >> 4));
builder.append(hexdigits.charAt(key[i] & 0x0f));
}
builder.append("], iv [");
for (int i = 0; i < key.length; i++) {
builder.append(hexdigits.charAt((iv[i] & 0xf0) >> 4));
builder.append(hexdigits.charAt(iv[i] & 0x0f));
}
builder.append("], clear ");
builder.append(Arrays.toString(numBytesOfClearData));
builder.append(", encrypted ");
builder.append(Arrays.toString(numBytesOfEncryptedData));
return builder.toString();
}
};
/**
* Similar to {@link #queueInputBuffer} but submits a buffer that is
* potentially encrypted.
* @param index The index of a client-owned input buffer previously returned
* in a call to {@link #dequeueInputBuffer}.
* @param offset The byte offset into the input buffer at which the data starts.
* @param info Metadata required to facilitate decryption, the object can be
* reused immediately after this call returns.
* @param presentationTimeUs The time at which this buffer should be rendered.
* @param flags A bitmask of flags {@link #BUFFER_FLAG_SYNC_FRAME},
* {@link #BUFFER_FLAG_CODEC_CONFIG} or {@link #BUFFER_FLAG_END_OF_STREAM}.
*/
public native final void queueSecureInputBuffer(
int index,
int offset,
CryptoInfo info,
long presentationTimeUs,
int flags) throws CryptoException;
/**
* Returns the index of an input buffer to be filled with valid data
* or -1 if no such buffer is currently available.
* This method will return immediately if timeoutUs == 0, wait indefinitely
* for the availability of an input buffer if timeoutUs < 0 or wait up
* to "timeoutUs" microseconds if timeoutUs > 0.
* @param timeoutUs The timeout in microseconds, a negative timeout indicates "infinite".
*/
public native final int dequeueInputBuffer(long timeoutUs);
/**
* If a non-negative timeout had been specified in the call
* to {@link #dequeueOutputBuffer}, indicates that the call timed out.
*/
public static final int INFO_TRY_AGAIN_LATER = -1;
/**
* The output format has changed, subsequent data will follow the new
* format. {@link #getOutputFormat} returns the new format.
*/
public static final int INFO_OUTPUT_FORMAT_CHANGED = -2;
/**
* The output buffers have changed, the client must refer to the new
* set of output buffers returned by {@link #getOutputBuffers} from
* this point on.
*/
public static final int INFO_OUTPUT_BUFFERS_CHANGED = -3;
/**
* Dequeue an output buffer, block at most "timeoutUs" microseconds.
* Returns the index of an output buffer that has been successfully
* decoded or one of the INFO_* constants below.
* @param info Will be filled with buffer meta data.
* @param timeoutUs The timeout in microseconds, a negative timeout indicates "infinite".
*/
public native final int dequeueOutputBuffer(
BufferInfo info, long timeoutUs);
/**
* If you are done with a buffer, use this call to return the buffer to
* the codec. If you previously specified a surface when configuring this
* video decoder you can optionally render the buffer.
* @param index The index of a client-owned output buffer previously returned
* in a call to {@link #dequeueOutputBuffer}.
* @param render If a valid surface was specified when configuring the codec,
* passing true renders this output buffer to the surface.
*/
public native final void releaseOutputBuffer(int index, boolean render);
/**
* Signals end-of-stream on input. Equivalent to submitting an empty buffer with
* {@link #BUFFER_FLAG_END_OF_STREAM} set. This may only be used with
* encoders receiving input from a Surface created by {@link #createInputSurface}.
*/
public native final void signalEndOfInputStream();
/**
* Call this after dequeueOutputBuffer signals a format change by returning
* {@link #INFO_OUTPUT_FORMAT_CHANGED}
*/
public final MediaFormat getOutputFormat() {
return new MediaFormat(getOutputFormatNative());
}
private native final Map