rewrite OggFromWebMWriter
* reduce the number of iterations over the output file (less seeking) * fix audio samples with size of 255 do not handled correctly in the segment table (allows writing audio streams with 70kbps and 160kbps bitrate) * add support for VORBIS codec metadata * write packets based on the timestamp
This commit is contained in:
kapodamy
parent
773aa1eff0
commit
dab53450c1
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@ -23,12 +23,16 @@ import javax.annotation.Nullable;
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public class OggFromWebMWriter implements Closeable {
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private static final byte FLAG_UNSET = 0x00;
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//private static final byte FLAG_CONTINUED = 0x01;
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private static final byte FLAG_CONTINUED = 0x01;
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private static final byte FLAG_FIRST = 0x02;
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private static final byte FLAG_LAST = 0x04;
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private final static byte SEGMENTS_PER_PACKET = 50;// used in ffmpeg, which is near 1 second at 48kHz
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private final static byte HEADER_CHECKSUM_OFFSET = 22;
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private final static byte HEADER_SIZE = 27;
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private final static short BUFFER_SIZE = 8 * 1024;// 8KiB
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private final static int TIME_SCALE_NS = 1000000000;
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private boolean done = false;
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private boolean parsed = false;
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@ -38,10 +42,23 @@ public class OggFromWebMWriter implements Closeable {
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private int sequence_count = 0;
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private final int STREAM_ID;
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private byte packet_flag = FLAG_FIRST;
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private int track_index = 0;
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private WebMReader webm = null;
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private WebMTrack webm_track = null;
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private int track_index = 0;
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private Segment webm_segment = null;
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private Cluster webm_cluster = null;
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private SimpleBlock webm_block = null;
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private long webm_block_last_timecode = 0;
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private long webm_block_near_duration = 0;
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private short segment_table_size = 0;
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private final byte[] segment_table = new byte[255];
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private long segment_table_next_timestamp = TIME_SCALE_NS;
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private final int[] crc32_table = new int[256];
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public OggFromWebMWriter(@NonNull SharpStream source, @NonNull SharpStream target) {
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if (!source.canRead() || !source.canRewind()) {
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@ -139,9 +156,8 @@ public class OggFromWebMWriter implements Closeable {
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float resolution;
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int read;
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byte[] buffer;
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int checksum;
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byte flag = FLAG_FIRST;// obligatory
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/* step 1: get the amount of frames per seconds */
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switch (webm_track.kind) {
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case Audio:
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resolution = getSampleFrequencyFromTrack(webm_track.bMetadata);
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@ -160,52 +176,65 @@ public class OggFromWebMWriter implements Closeable {
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throw new RuntimeException("not implemented");
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}
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/* step 1.1: write codec init data, in most cases must be present */
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/* step 2a: create packet with code init data */
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ArrayList<byte[]> data_extra = new ArrayList<>(4);
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if (webm_track.codecPrivate != null) {
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addPacketSegment(webm_track.codecPrivate.length);
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dump_packetHeader(flag, 0x00, webm_track.codecPrivate);
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flag = FLAG_UNSET;
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ByteBuffer buff = byte_buffer(HEADER_SIZE + segment_table_size + webm_track.codecPrivate.length);
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make_packetHeader(0x00, buff, webm_track.codecPrivate);
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data_extra.add(buff.array());
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}
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/* step 1.2: write metadata */
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/* step 2b: create packet with metadata */
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buffer = make_metadata();
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if (buffer != null) {
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addPacketSegment(buffer.length);
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dump_packetHeader(flag, 0x00, buffer);
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flag = FLAG_UNSET;
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ByteBuffer buff = byte_buffer(HEADER_SIZE + segment_table_size + buffer.length);
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make_packetHeader(0x00, buff, buffer);
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data_extra.add(buff.array());
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}
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buffer = new byte[8 * 1024];
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/* step 1.3: write headers */
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long approx_packets = webm_segment.info.duration / webm_segment.info.timecodeScale;
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approx_packets = approx_packets / (approx_packets / SEGMENTS_PER_PACKET);
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ArrayList<Long> pending_offsets = new ArrayList<>((int) approx_packets);
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ArrayList<Integer> pending_checksums = new ArrayList<>((int) approx_packets);
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ArrayList<Short> data_offsets = new ArrayList<>((int) approx_packets);
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int page_size = 0;
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/* step 3: calculate amount of packets */
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SimpleBlock bloq;
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int reserve_header = 0;
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int headers_amount = 0;
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while (webm_segment != null) {
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bloq = getNextBlock();
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if (bloq != null && addPacketSegment(bloq.dataSize)) {
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page_size += bloq.dataSize;
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if (segment_table_size < SEGMENTS_PER_PACKET) {
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continue;
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}
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// calculate the current packet duration using the next block
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bloq = getNextBlock();
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if (addPacketSegment(bloq)) {
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continue;
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}
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reserve_header += HEADER_SIZE + segment_table_size;// header size
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clearSegmentTable();
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webm_block = bloq;
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headers_amount++;
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}
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/* step 4: create packet headers */
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rewind_source();
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ByteBuffer headers = byte_buffer(reserve_header);
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short[] headers_size = new short[headers_amount];
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int header_index = 0;
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while (webm_segment != null) {
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bloq = getNextBlock();
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if (addPacketSegment(bloq)) {
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continue;
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}
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// calculate the current packet duration using the next block
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double elapsed_ns = webm_track.codecDelay;
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if (bloq == null) {
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flag = FLAG_LAST;
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packet_flag = FLAG_LAST;// note: if the flag is FLAG_CONTINUED, is changed
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elapsed_ns += webm_block_last_timecode;
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if (webm_track.defaultDuration > 0) {
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@ -219,84 +248,83 @@ public class OggFromWebMWriter implements Closeable {
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}
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// get the sample count in the page
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elapsed_ns = (elapsed_ns / 1000000000d) * resolution;
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elapsed_ns = Math.ceil(elapsed_ns);
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long offset = output_offset + HEADER_CHECKSUM_OFFSET;
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pending_offsets.add(offset);
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checksum = dump_packetHeader(flag, (long) elapsed_ns, null);
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pending_checksums.add(checksum);
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data_offsets.add((short) (output_offset - offset));
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// reserve space in the page
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while (page_size > 0) {
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int write = Math.min(page_size, buffer.length);
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out_write(buffer, write);
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page_size -= write;
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}
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elapsed_ns = elapsed_ns / TIME_SCALE_NS;
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elapsed_ns = Math.ceil(elapsed_ns * resolution);
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// create header
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headers_size[header_index++] = make_packetHeader((long) elapsed_ns, headers, null);
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webm_block = bloq;
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}
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/* step 2.1: write stream data */
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output.rewind();
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output_offset = 0;
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source.rewind();
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/* step 5: calculate checksums */
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rewind_source();
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webm = new WebMReader(source);
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webm.parse();
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webm_track = webm.selectTrack(track_index);
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int offset = 0;
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buffer = new byte[BUFFER_SIZE];
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for (int i = 0; i < pending_offsets.size(); i++) {
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checksum = pending_checksums.get(i);
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segment_table_size = 0;
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for (header_index = 0; header_index < headers_size.length; header_index++) {
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int checksum_offset = offset + HEADER_CHECKSUM_OFFSET;
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int checksum = headers.getInt(checksum_offset);
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out_seek(pending_offsets.get(i) + data_offsets.get(i));
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while (segment_table_size < SEGMENTS_PER_PACKET) {
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while (webm_segment != null) {
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bloq = getNextBlock();
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if (bloq == null || !addPacketSegment(bloq.dataSize)) {
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webm_block = bloq;// use this block later (if not null)
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if (!addPacketSegment(bloq)) {
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clearSegmentTable();
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webm_block = bloq;
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break;
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}
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// NOTE: calling bloq.data.close() is unnecessary
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while ((read = bloq.data.read(buffer)) != -1) {
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out_write(buffer, read);
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checksum = calc_crc32(checksum, buffer, read);
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// calculate page checksum
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while ((read = bloq.data.read(buffer)) > 0) {
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checksum = calc_crc32(checksum, buffer, 0, read);
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}
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}
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pending_checksums.set(i, checksum);
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headers.putInt(checksum_offset, checksum);
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offset += headers_size[header_index];
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}
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/* step 2.2: write every checksum */
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output.rewind();
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output_offset = 0;
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buffer = new byte[4];
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/* step 6: write extra headers */
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rewind_source();
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ByteBuffer buff = ByteBuffer.wrap(buffer);
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buff.order(ByteOrder.LITTLE_ENDIAN);
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for (byte[] buff : data_extra) {
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output.write(buff);
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}
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for (int i = 0; i < pending_checksums.size(); i++) {
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out_seek(pending_offsets.get(i));
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buff.putInt(0, pending_checksums.get(i));
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out_write(buffer);
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/* step 7: write stream packets */
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byte[] headers_buffers = headers.array();
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offset = 0;
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buffer = new byte[BUFFER_SIZE];
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for (header_index = 0; header_index < headers_size.length; header_index++) {
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output.write(headers_buffers, offset, headers_size[header_index]);
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offset += headers_size[header_index];
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while (webm_segment != null) {
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bloq = getNextBlock();
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if (addPacketSegment(bloq)) {
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while ((read = bloq.data.read(buffer)) > 0) {
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output.write(buffer, 0, read);
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}
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} else {
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clearSegmentTable();
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webm_block = bloq;
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break;
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}
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}
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}
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}
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private int dump_packetHeader(byte flag, long gran_pos, byte[] immediate_page) throws IOException {
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ByteBuffer buffer = ByteBuffer.allocate(27 + segment_table_size);
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private short make_packetHeader(long gran_pos, ByteBuffer buffer, byte[] immediate_page) {
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int offset = buffer.position();
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short length = HEADER_SIZE;
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buffer.putInt(0x4F676753);// "OggS" binary string
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buffer.putInt(0x5367674f);// "OggS" binary string in little-endian
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buffer.put((byte) 0x00);// version
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buffer.put(flag);// type
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buffer.order(ByteOrder.LITTLE_ENDIAN);
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buffer.put(packet_flag);// type
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buffer.putLong(gran_pos);// granulate position
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@ -305,28 +333,24 @@ public class OggFromWebMWriter implements Closeable {
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buffer.putInt(0x00);// page checksum
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buffer.order(ByteOrder.BIG_ENDIAN);
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buffer.put((byte) segment_table_size);// segment table
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buffer.put(segment_table, 0, segment_table_size);// segment size
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segment_table_size = 0;// clear segment table for next header
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length += segment_table_size;
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byte[] buff = buffer.array();
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int checksum_crc32 = calc_crc32(0x00, buff, buff.length);
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clearSegmentTable();// clear segment table for next header
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int checksum_crc32 = calc_crc32(0x00, buffer.array(), offset, length);
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if (immediate_page != null) {
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checksum_crc32 = calc_crc32(checksum_crc32, immediate_page, immediate_page.length);
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buffer.order(ByteOrder.LITTLE_ENDIAN);
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buffer.putInt(HEADER_CHECKSUM_OFFSET, checksum_crc32);
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out_write(buff);
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out_write(immediate_page);
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return 0;
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checksum_crc32 = calc_crc32(checksum_crc32, immediate_page, 0, immediate_page.length);
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System.arraycopy(immediate_page, 0, buffer.array(), length, immediate_page.length);
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segment_table_next_timestamp -= TIME_SCALE_NS;
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}
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out_write(buff);
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return checksum_crc32;
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buffer.putInt(offset + HEADER_CHECKSUM_OFFSET, checksum_crc32);
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return length;
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}
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@Nullable
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@ -334,7 +358,7 @@ public class OggFromWebMWriter implements Closeable {
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if ("A_OPUS".equals(webm_track.codecId)) {
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return new byte[]{
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0x4F, 0x70, 0x75, 0x73, 0x54, 0x61, 0x67, 0x73,// "OpusTags" binary string
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0x07, 0x00, 0x00, 0x00,// writting application string size
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0x07, 0x00, 0x00, 0x00,// writing application string size
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0x4E, 0x65, 0x77, 0x50, 0x69, 0x70, 0x65,// "NewPipe" binary string
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0x00, 0x00, 0x00, 0x00// additional tags count (zero means no tags)
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};
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@ -342,15 +366,15 @@ public class OggFromWebMWriter implements Closeable {
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return new byte[]{
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0x03,// ????????
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0x76, 0x6f, 0x72, 0x62, 0x69, 0x73,// "vorbis" binary string
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0x07, 0x00, 0x00, 0x00,// writting application string size
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0x07, 0x00, 0x00, 0x00,// writing application string size
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0x4E, 0x65, 0x77, 0x50, 0x69, 0x70, 0x65,// "NewPipe" binary string
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0x01, 0x00, 0x00, 0x00,// additional tags count (zero means no tags)
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/*
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// whole file duration (not implemented)
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0x44,// tag string size
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0x55, 0x52, 0x41, 0x54, 0x49, 0x4F, 0x4E, 0x3D, 0x30, 0x30, 0x3A, 0x30, 0x30, 0x3A, 0x30,
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0x30, 0x2E, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30
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// whole file duration (not implemented)
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0x44,// tag string size
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0x55, 0x52, 0x41, 0x54, 0x49, 0x4F, 0x4E, 0x3D, 0x30, 0x30, 0x3A, 0x30, 0x30, 0x3A, 0x30,
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0x30, 0x2E, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30
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*/
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0x0F,// tag string size
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0x00, 0x00, 0x00, 0x45, 0x4E, 0x43, 0x4F, 0x44, 0x45, 0x52, 0x3D,// "ENCODER=" binary string
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@ -363,13 +387,26 @@ public class OggFromWebMWriter implements Closeable {
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return null;
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}
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//<editor-fold defaultstate="collapsed" desc="WebM track handling">
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private Segment webm_segment = null;
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private Cluster webm_cluter = null;
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private SimpleBlock webm_block = null;
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private long webm_block_last_timecode = 0;
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private long webm_block_near_duration = 0;
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private void rewind_source() throws IOException {
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source.rewind();
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webm = new WebMReader(source);
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webm.parse();
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webm_track = webm.selectTrack(track_index);
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webm_segment = webm.getNextSegment();
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webm_cluster = null;
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webm_block = null;
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webm_block_last_timecode = 0L;
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segment_table_next_timestamp = TIME_SCALE_NS;
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}
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private ByteBuffer byte_buffer(int size) {
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return ByteBuffer.allocate(size).order(ByteOrder.LITTLE_ENDIAN);
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}
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//<editor-fold defaultstate="collapsed" desc="WebM track handling">
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@Nullable
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private SimpleBlock getNextBlock() throws IOException {
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SimpleBlock res;
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@ -386,17 +423,17 @@ public class OggFromWebMWriter implements Closeable {
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}
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}
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if (webm_cluter == null) {
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webm_cluter = webm_segment.getNextCluster();
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if (webm_cluter == null) {
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if (webm_cluster == null) {
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webm_cluster = webm_segment.getNextCluster();
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if (webm_cluster == null) {
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webm_segment = null;
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return getNextBlock();
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}
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}
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res = webm_cluter.getNextSimpleBlock();
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res = webm_cluster.getNextSimpleBlock();
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if (res == null) {
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webm_cluter = null;
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webm_cluster = null;
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return getNextBlock();
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}
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@ -421,49 +458,64 @@ public class OggFromWebMWriter implements Closeable {
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}
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//</editor-fold>
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//<editor-fold defaultstate="collapsed" desc="Segment table store">
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private int segment_table_size = 0;
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private final byte[] segment_table = new byte[255];
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//<editor-fold defaultstate="collapsed" desc="Segment table writing">
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private void clearSegmentTable() {
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if (packet_flag != FLAG_CONTINUED) {
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segment_table_next_timestamp += TIME_SCALE_NS;
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packet_flag = FLAG_UNSET;
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}
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segment_table_size = 0;
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}
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private boolean addPacketSegment(long size) {
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// check if possible add the segment, without overflow the table
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private boolean addPacketSegment(SimpleBlock block) {
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if (block == null) {
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return false;
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}
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long timestamp = block.absoluteTimeCodeNs + webm_track.codecDelay;
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if (timestamp >= segment_table_next_timestamp) {
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return false;
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}
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boolean result = addPacketSegment((int) block.dataSize);
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if (!result && segment_table_next_timestamp < timestamp) {
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// WARNING: ¡¡¡¡ not implemented (lack of documentation) !!!!
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packet_flag = FLAG_CONTINUED;
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}
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||||
return result;
|
||||
}
|
||||
|
||||
private boolean addPacketSegment(int size) {
|
||||
int available = (segment_table.length - segment_table_size) * 255;
|
||||
boolean extra = size == 255;
|
||||
|
||||
if (extra) {
|
||||
// add a zero byte entry in the table
|
||||
// required to indicate the sample size is exactly 255
|
||||
available -= 255;
|
||||
}
|
||||
|
||||
// check if possible add the segment, without overflow the table
|
||||
if (available < size) {
|
||||
return false;// not enough space on the page
|
||||
}
|
||||
|
||||
while (size > 0) {
|
||||
for (; size > 0; size -= 255) {
|
||||
segment_table[segment_table_size++] = (byte) Math.min(size, 255);
|
||||
size -= 255;
|
||||
}
|
||||
|
||||
if (extra) {
|
||||
segment_table[segment_table_size++] = 0x00;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
//</editor-fold>
|
||||
|
||||
//<editor-fold defaultstate="collapsed" desc="Output handling">
|
||||
private long output_offset = 0;
|
||||
|
||||
private void out_write(byte[] buffer) throws IOException {
|
||||
output.write(buffer);
|
||||
output_offset += buffer.length;
|
||||
}
|
||||
|
||||
private void out_write(byte[] buffer, int size) throws IOException {
|
||||
output.write(buffer, 0, size);
|
||||
output_offset += size;
|
||||
}
|
||||
|
||||
private void out_seek(long offset) throws IOException {
|
||||
//if (output.canSeek()) { output.seek(offset); }
|
||||
output.skip(offset - output_offset);
|
||||
output_offset = offset;
|
||||
}
|
||||
//</editor-fold>
|
||||
|
||||
//<editor-fold defaultstate="collapsed" desc="Checksum CRC32">
|
||||
private final int[] crc32_table = new int[256];
|
||||
|
||||
private void populate_crc32_table() {
|
||||
for (int i = 0; i < 0x100; i++) {
|
||||
int crc = i << 24;
|
||||
|
|
@ -476,10 +528,12 @@ public class OggFromWebMWriter implements Closeable {
|
|||
}
|
||||
}
|
||||
|
||||
private int calc_crc32(int initial_crc, byte[] buffer, int size) {
|
||||
for (int i = 0; i < size; i++) {
|
||||
private int calc_crc32(int initial_crc, byte[] buffer, int offset, int size) {
|
||||
size += offset;
|
||||
|
||||
for (; offset < size; offset++) {
|
||||
int reg = (initial_crc >>> 24) & 0xff;
|
||||
initial_crc = (initial_crc << 8) ^ crc32_table[reg ^ (buffer[i] & 0xff)];
|
||||
initial_crc = (initial_crc << 8) ^ crc32_table[reg ^ (buffer[offset] & 0xff)];
|
||||
}
|
||||
|
||||
return initial_crc;
|
||||
|
|
|
|||
|
|
@ -11,7 +11,7 @@ import java.nio.ByteBuffer;
|
|||
class OggFromWebmDemuxer extends Postprocessing {
|
||||
|
||||
OggFromWebmDemuxer() {
|
||||
super(false, true, ALGORITHM_OGG_FROM_WEBM_DEMUXER);
|
||||
super(true, true, ALGORITHM_OGG_FROM_WEBM_DEMUXER);
|
||||
}
|
||||
|
||||
@Override
|
||||
|
|
@ -24,7 +24,7 @@ class OggFromWebmDemuxer extends Postprocessing {
|
|||
|
||||
switch (buffer.getInt()) {
|
||||
case 0x1a45dfa3:
|
||||
return true;// webm
|
||||
return true;// webm/mkv
|
||||
case 0x4F676753:
|
||||
return false;// ogg
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue