초록 ▼

A multimedia system including an audio/video decoder/decompresser for decoding/decompressing a compressed encoded audio/video data stream to generate video images for display and audio signals for audible reproduction. The multimedia system includes an integrated system and video decoder with an aud

A multimedia system including an audio/video decoder/decompresser for decoding/decompressing a compressed encoded audio/video data stream to generate video images for display and audio signals for audible reproduction. The multimedia system includes an integrated system and video decoder with an audio/video synchronization circuit for substantially synchronizing the display of video images with audio playback. Latency between Audio and Video decompression/decoding may be adjusted dynamically by internal hardware. Hardware signals indicating the need to skip or repeat a frame or frames of video or audio data are fed to a hardware circuit which may increment or decrement a latency value accordingly. The latency value is thus stepwise incremented or decremented until no further frame skips/repeats occur. The hardware implementation allows for better matching of latency value to audio and video decoder, frees up software for other tasks and reduces software code requirements. In addition, changes to the audio and video data paths (e.g., switching to an auxiliary audio decoder) are automatically and quickly compensated for. The hardware implementation may provide for additional levels of latency adjustment.

대표청구항 ▼

A method for controlling playback of audio and video signals from an encoded data stream comprising at least audio data packets, video data packets, audio presentation time stamps and video presentation time stamps, said apparatus comprising: separating the encoded data stream into an encoded audio

A method for controlling playback of audio and video signals from an encoded data stream comprising at least audio data packets, video data packets, audio presentation time stamps and video presentation time stamps, said apparatus comprising: separating the encoded data stream into an encoded audio data stream comprising at least the audio data packets and audio presentation time stamps and an encoded video data stream comprising at least the video data packets and video presentation time stamps; combining a decoder latency value to one of the video and audio presentation time stamp values to produce a normalized presentation time stamp value; subtracting the normalized presentation time stamp value from the other of the audio and video presentation time stamp values to produce a difference value; comparing the difference value with a predetermined time drift threshold and outputting a frame skip/repeat signal if the difference value exceeds the pre-determined time drift threshold; and modifying the latency value if the frame skip/repeat signal is generated in the comparing step.