System and method for using HDMI arc for estimating latency
Disclosed is a method that includes receiving an audio video stream, decoding the audio video stream to yield decoded video and decoded audio, transmitting the decoded video on a video cable to a display, transmitting a signal, such as, for example, a signal on an audio channel of the video cable, identifying an impulse response based on a received signal responsive to the transmitting of the signal, identifying a delay amount based on the impulse response and transmitting the decoded audio to a loudspeaker according to the delay amount. The cable can include an HDMI cable with the audio return channel (ARC) capability.
1. A method comprising:
receiving an audio video stream;
decoding the audio video stream to yield decoded video and decoded audio;
transmitting the decoded video on a cable to a display;
transmitting a signal on an audio channel of the cable to the display;
receiving a return signal from the display over an audio return channel of the cable responsive to the transmitting a signal;
identifying an impulse response based on the return signal responsive to the transmitting of the signal;
identifying a delay amount created by transmitting a signal and receiving the return signal over the cable based on the impulse response; and
transmitting the decoded audio to a speaker according to the delay amount to synchronize the decoded video and the decoded audio.
2. The method of claim 1 , wherein identifying the impulse response is based upon applying a Hadamard transformation of the return signal based on the transmitting of the signal on the audio channel of the cable.
3. The method of claim 1 , wherein the display comprises a television.
4. The method of claim 1 , wherein the cable comprises an HDMI cable.
5. The method of claim 1 , wherein the speaker is independent of the display.
6. The method of claim 1 , wherein the signal comprises a maximum length sequence signal.
7. A system comprising:
at least one processor; and
a computer-readable storage device instructions which, when executed by the at least one processor, cause the at least one processor to perform operations comprising:
receiving an audio video stream;
decoding the audio video stream to yield decoded and decoded audio;
transmitting the decoded video on a cable to a display;
transmitting a signal on an audio channel of the cable to the display;
receiving a return signal from the display over an audio return channel of the cable responsive to transmitting a signal;
identifying an impulse response based on the return signal responsive to the transmitting of the signal;
identifying a delay amount created by transmitting a signal and receiving the return signal over the cable based on the impulse response; and
transmitting the decoded audio to a speaker according to the delay amount to synchronize the decoded video and the decoded audio.
8. The system of claim 7 , wherein identifying the impulse response is based upon applying a Hadamard transformation of the return signal based on the transmitting of the signal on the audio channel of the cable.
9. The system of claim 7 , wherein the display comprises a television.
10. The system of claim 7 , wherein the cable comprises an HDMI cable.
11. The system of claim 7 , wherein the speaker is independent of the display.
12. The system of claim 7 , wherein the signal comprises a maximum length sequence signal.
13. A non-transitory computer-readable storage device storing instructions which, when executed by at least one processor, cause the at least one processor to perform operations comprising:
receiving an audio video stream;
decoding the audio video stream to yield decoded video and decoded audio;
transmitting the decoded video on a cable to a display;
transmitting a signal on the cable to the display;
receiving a return signal from the display over an audio return channel of the cable responsive to the transmitting of a signal;
identifying an impulse response based on the return signal responsive to the transmitting of the signal;
identifying a delay amount created by transmitting a signal and receiving the return signal over the cable based on the impulse response; and
transmitting the decoded audio to a speaker according to the delay amount to synchronize the decoded video and the decoded audio.
14. The non-transitory computer-readable storage device of claim 13 , wherein identifying the impulse response is based upon applying a Hadamard transformation of the return signal being responsive to the transmitting of the signal of the cable.
15. The non-transitory computer-readable storage device of claim 13 , wherein the display comprises a television.
16. The non-transitory computer-readable storage device of claim 13 , wherein the cable comprises an HDMI cable.
17. The non-transitory computer-readable storage device of claim 13 , wherein the speaker is independent of the display.