Class TimestampAdjuster


  • public final class TimestampAdjuster
    extends Object
    Adjusts and offsets sample timestamps. MPEG-2 TS timestamps scaling and adjustment is supported, taking into account timestamp rollover.
    • Constructor Detail

      • TimestampAdjuster

        public TimestampAdjuster​(long firstSampleTimestampUs)
        Parameters:
        firstSampleTimestampUs - The desired value of the first adjusted sample timestamp in microseconds, or MODE_NO_OFFSET if timestamps should not be offset, or MODE_SHARED if the adjuster will be used in shared mode.
    • Method Detail

      • sharedInitializeOrWait

        public void sharedInitializeOrWait​(boolean canInitialize,
                                           long nextSampleTimestampUs)
                                    throws InterruptedException
        For shared timestamp adjusters, performs necessary initialization actions for a caller.
        • If the adjuster has already established a timestamp offset then this method is a no-op.
        • If canInitialize is true and the adjuster has not yet established a timestamp offset, then the adjuster records the desired first sample timestamp for the calling thread and returns to allow the caller to proceed. If the timestamp offset has still not been established when the caller attempts to adjust its first timestamp, then the recorded timestamp is used to set it.
        • If canInitialize is false and the adjuster has not yet established a timestamp offset, then the call blocks until the timestamp offset is set.
        Parameters:
        canInitialize - Whether the caller is able to initialize the adjuster, if needed.
        nextSampleTimestampUs - The desired timestamp for the next sample loaded by the calling thread, in microseconds. Only used if canInitialize is true.
        Throws:
        InterruptedException - If the thread is interrupted whilst blocked waiting for initialization to complete.
      • getFirstSampleTimestampUs

        public long getFirstSampleTimestampUs()
        Returns the value of the first adjusted sample timestamp in microseconds, or C.TIME_UNSET if timestamps will not be offset or if the adjuster is in shared mode.
      • getLastAdjustedTimestampUs

        public long getLastAdjustedTimestampUs()
        Returns the last adjusted timestamp, in microseconds. If no timestamps have been adjusted yet then the result of getFirstSampleTimestampUs() is returned.
      • getTimestampOffsetUs

        public long getTimestampOffsetUs()
        Returns the offset between the input of adjustSampleTimestamp(long) and its output, or C.TIME_UNSET if the offset has not yet been determined.
      • reset

        public void reset​(long firstSampleTimestampUs)
        Resets the instance.
        Parameters:
        firstSampleTimestampUs - The desired value of the first adjusted sample timestamp after this reset in microseconds, or MODE_NO_OFFSET if timestamps should not be offset, or MODE_SHARED if the adjuster will be used in shared mode.
      • adjustTsTimestamp

        public long adjustTsTimestamp​(long pts90Khz)
        Scales and offsets an MPEG-2 TS presentation timestamp considering wraparound.
        Parameters:
        pts90Khz - A 90 kHz clock MPEG-2 TS presentation timestamp.
        Returns:
        The adjusted timestamp in microseconds.
      • adjustSampleTimestamp

        public long adjustSampleTimestamp​(long timeUs)
        Offsets a timestamp in microseconds.
        Parameters:
        timeUs - The timestamp to adjust in microseconds.
        Returns:
        The adjusted timestamp in microseconds.
      • ptsToUs

        public static long ptsToUs​(long pts)
        Converts a 90 kHz clock timestamp to a timestamp in microseconds.
        Parameters:
        pts - A 90 kHz clock timestamp.
        Returns:
        The corresponding value in microseconds.
      • usToWrappedPts

        public static long usToWrappedPts​(long us)
        Converts a timestamp in microseconds to a 90 kHz clock timestamp, performing wraparound to keep the result within 33-bits.
        Parameters:
        us - A value in microseconds.
        Returns:
        The corresponding value as a 90 kHz clock timestamp, wrapped to 33 bits.
      • usToNonWrappedPts

        public static long usToNonWrappedPts​(long us)
        Converts a timestamp in microseconds to a 90 kHz clock timestamp.

        Does not perform any wraparound. To get a 90 kHz timestamp suitable for use with MPEG-TS, use usToWrappedPts(long).

        Parameters:
        us - A value in microseconds.
        Returns:
        The corresponding value as a 90 kHz clock timestamp.