Let apps provide a custom data source for extractors (c209a06c) · Commits · e / os / android_frameworks_base

media/java/android/media/DataSource.java

0 → 100644

+43 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2012 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 android.media;

		import java.io.Closeable;

		/**
		* An abstraction for a media data source, e.g. a file or an http stream
		* {@hide}
		*/
		public interface DataSource extends Closeable {
		/**
		* Reads data from the data source at the requested position
		*
		* @param offset where in the source to read
		* @param buffer the buffer to read the data into
		* @param size how many bytes to read
		* @return the number of bytes read, or -1 if there was an error
		*/
		public int readAt(long offset, byte[] buffer, int size);

		/**
		* Gets the size of the data source.
		*
		* @return size of data source, or -1 if the length is unknown
		*/
		public long getSize();
		}

media/java/android/media/MediaExtractor.java

+7 −0

Original line number	Diff line number	Diff line
		@@ -22,6 +22,7 @@ import android.content.res.AssetFileDescriptor;
		import android.media.MediaCodec;
		import android.media.MediaFormat;
		import android.net.Uri;

		import java.io.FileDescriptor;
		import java.io.IOException;
		import java.nio.ByteBuffer;
		@@ -59,6 +60,12 @@ final public class MediaExtractor {
		native_setup();
		}

		/**
		* Sets the DataSource object to be used as the data source for this extractor
		* {@hide}
		*/
		public native final void setDataSource(DataSource source);

		/**
		* Sets the data source as a content Uri.
		*

media/jni/android_media_MediaExtractor.cpp

+100 −0

Original line number	Diff line number	Diff line
		@@ -44,6 +44,72 @@ struct fields_t {

		static fields_t gFields;

		class JavaDataSourceBridge : public DataSource {
		jmethodID mReadMethod;
		jmethodID mGetSizeMethod;
		jmethodID mCloseMethod;
		jobject mDataSource;
		public:
		JavaDataSourceBridge(JNIEnv *env, jobject source) {
		mDataSource = env->NewGlobalRef(source);

		jclass datasourceclass = env->GetObjectClass(mDataSource);
		CHECK(datasourceclass != NULL);

		mReadMethod = env->GetMethodID(datasourceclass, "readAt", "(J[BI)I");
		CHECK(mReadMethod != NULL);

		mGetSizeMethod = env->GetMethodID(datasourceclass, "getSize", "()J");
		CHECK(mGetSizeMethod != NULL);

		mCloseMethod = env->GetMethodID(datasourceclass, "close", "()V");
		CHECK(mCloseMethod != NULL);
		}

		~JavaDataSourceBridge() {
		JNIEnv *env = AndroidRuntime::getJNIEnv();
		env->CallVoidMethod(mDataSource, mCloseMethod);
		env->DeleteGlobalRef(mDataSource);
		}

		virtual status_t initCheck() const {
		return OK;
		}

		virtual ssize_t readAt(off64_t offset, void* buffer, size_t size) {
		JNIEnv *env = AndroidRuntime::getJNIEnv();

		// XXX could optimize this by reusing the same array
		jbyteArray byteArrayObj = env->NewByteArray(size);
		env->DeleteLocalRef(env->GetObjectClass(mDataSource));
		env->DeleteLocalRef(env->GetObjectClass(byteArrayObj));
		ssize_t numread = env->CallIntMethod(mDataSource, mReadMethod, offset, byteArrayObj, size);
		env->GetByteArrayRegion(byteArrayObj, 0, size, (jbyte*) buffer);
		env->DeleteLocalRef(byteArrayObj);
		if (env->ExceptionCheck()) {
		ALOGW("Exception occurred while reading %d at %lld", size, offset);
		LOGW_EX(env);
		env->ExceptionClear();
		return -1;
		}
		return numread;
		}

		virtual status_t getSize(off64_t *size) {
		JNIEnv *env = AndroidRuntime::getJNIEnv();

		CHECK(size != NULL);

		int64_t len = env->CallLongMethod(mDataSource, mGetSizeMethod);
		if (len < 0) {
		*size = ERROR_UNSUPPORTED;
		} else {
		*size = len;
		}
		return OK;
		}
		};

		////////////////////////////////////////////////////////////////////////////////

		JMediaExtractor::JMediaExtractor(JNIEnv *env, jobject thiz)
		@@ -76,6 +142,10 @@ status_t JMediaExtractor::setDataSource(int fd, off64_t offset, off64_t size) {
		return mImpl->setDataSource(fd, offset, size);
		}

		status_t JMediaExtractor::setDataSource(const sp<DataSource> &datasource) {
		return mImpl->setDataSource(datasource);
		}

		size_t JMediaExtractor::countTracks() const {
		return mImpl->countTracks();
		}
		@@ -625,6 +695,33 @@ static void android_media_MediaExtractor_setDataSourceFd(
		}
		}

		static void android_media_MediaExtractor_setDataSourceCallback(
		JNIEnv *env, jobject thiz,
		jobject callbackObj) {
		sp<JMediaExtractor> extractor = getMediaExtractor(env, thiz);

		if (extractor == NULL) {
		jniThrowException(env, "java/lang/IllegalStateException", NULL);
		return;
		}

		if (callbackObj == NULL) {
		jniThrowException(env, "java/lang/IllegalArgumentException", NULL);
		return;
		}

		sp<JavaDataSourceBridge> bridge = new JavaDataSourceBridge(env, callbackObj);
		status_t err = extractor->setDataSource(bridge);

		if (err != OK) {
		jniThrowException(
		env,
		"java/io/IOException",
		"Failed to instantiate extractor.");
		return;
		}
		}

		static jlong android_media_MediaExtractor_getCachedDurationUs(
		JNIEnv *env, jobject thiz) {
		sp<JMediaExtractor> extractor = getMediaExtractor(env, thiz);
		@@ -713,6 +810,9 @@ static JNINativeMethod gMethods[] = {
		{ "setDataSource", "(Ljava/io/FileDescriptor;JJ)V",
		(void *)android_media_MediaExtractor_setDataSourceFd },

		{ "setDataSource", "(Landroid/media/DataSource;)V",
		(void *)android_media_MediaExtractor_setDataSourceCallback },

		{ "getCachedDuration", "()J",
		(void *)android_media_MediaExtractor_getCachedDurationUs },

media/jni/android_media_MediaExtractor.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@

		#include <media/stagefright/foundation/ABase.h>
		#include <media/stagefright/MediaSource.h>
		#include <media/stagefright/DataSource.h>
		#include <utils/Errors.h>
		#include <utils/KeyedVector.h>
		#include <utils/RefBase.h>
		@@ -39,6 +40,7 @@ struct JMediaExtractor : public RefBase {
		const KeyedVector<String8, String8> *headers);

		status_t setDataSource(int fd, off64_t offset, off64_t size);
		status_t setDataSource(const sp<DataSource> &source);

		size_t countTracks() const;
		status_t getTrackFormat(size_t index, jobject *format) const;