AVSamples.java

/*
 * Copyright (c) 2011 Michael Zucchi
 *
 * This file is part of jjmpeg, a java binding to ffmpeg's libraries.
 *
 * jjmpeg 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 3 of the License, or
 * (at your option) any later version.
 *
 * jjmpeg 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 jjmpeg.  If not, see <http://www.gnu.org/licenses/>.
 */
package au.notzed.jjmpeg;

import java.nio.Buffer;
import java.nio.ByteBuffer;

class AVSamplesNative extends AVNative {

	public AVSamplesNative(AVObject jobject, ByteBuffer p) {
		super(jobject, p);
	}

	@Override
	public void dispose() {
		if (p != null) {
			super.dispose();
			_free(p);
		}
	}
}

/**
 * Holder for audio samples memory, which has some specific memory
 * allocation requirements.
 * @author notzed
 */
public class AVSamples extends AVObject {

	final SampleFormat format;
	Buffer samples;

	public AVSamples(SampleFormat format) {
		setNative(new AVSamplesNative(this, AVNative._malloc(AVCodecContext.AVCODEC_MAX_AUDIO_FRAME_SIZE * 2)));
		this.format = format;

		samples = format.getBuffer(n.p);
	}

	public AVSamples(SampleFormat format, int channels, int frameSize) {
		setNative(new AVSamplesNative(this, AVNative._malloc(format.getByteSize() * channels * frameSize)));
		this.format = format;
		samples = format.getBuffer(n.p);
	}

	public ByteBuffer getBuffer() {
		return n.p;
	}

	public Buffer getSamples() {
		return samples;
	}

	public SampleFormat getFormat() {
		return format;
	}

	/**
	 * Drain the samples from src into this.
	 * 
	 * This is called repeatedly to create full sample buffers for
	 * encoding.
	 * 
	 * @param src
	 * @return true if this is now full and can be encoded.  It also
	 * means src may not be fully drained, and so should be called again.
	 */
	public boolean fill(AVSamples src) {
		/*
		 * You know, sometimes when you try to write a fairly simple bit
		 * of code using an existing api you have to wonder:
		 *   just what the fuck were they thinking?
		 */
		ByteBuffer obuf = getBuffer();
		ByteBuffer sbuf = src.getBuffer();
		int dremaining = obuf.capacity() - obuf.position();
		int sremaining = sbuf.remaining();

		if (sremaining > 0) {
			ByteBuffer ssbuf = sbuf.slice();
			int len = Math.min(sremaining, dremaining);

			ssbuf.limit(ssbuf.position() + len);
			sbuf.position(sbuf.position() + len);

			obuf.put(ssbuf);

			if (!obuf.hasRemaining()) {
				obuf.rewind();
				obuf.limit(obuf.capacity());
				return true;
			}
		}
		return false;
	}

	/**
	 * Pad out the rest of the buffer with 0.
	 */
	public void pad() {
		ByteBuffer obuf = getBuffer();
		for (int i = obuf.position(); i < obuf.capacity(); i++) {
			obuf.put(i, (byte) 0);
		}
	}
}