Clock synchronization method for use in communication system for transmitting at least one of video data and audio data

A communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting a video packet Pvideo to the sink device, to a header part of the video packet Pvideo as a time stamp value, and transmits the video packet Pvideo to the sink device, and
• wherein the sink device receives the video packet Pvideo, extracts the time stamp value Csource(t) from the header part of the video packet Pvideo, generates a fixed reference clock CLKref with a predetermined first frequency division parameter based on the counted value Csource(t) of the transmitting counter using a first PLL circuit, and generates the clock CLKpixel for the pixel data of the source device with a predetermined second frequency division parameter based on the reference clock CLKref using a second PLL circuit.

A communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKaudio for audio data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting an audio packet Paudio to the sink device, to a header part of the audio packet Pvideo as a time stamp value, and transmits the audio packet Paudio to the sink device, and
• wherein the sink device receives the audio packet Paudio, extracts the time stamp value Csource(t) from the header part of the audio packet Paudio, generates a fixed reference clock CLKref based on the time stamp value Csource(t) using a first PLL circuit, and generates the clock CLKaudio for the audio data of the source device based on the reference clock CLKref using a second PLL circuit.

A communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting a mixture packet Pav including video data and audio data to the sink device, to a header part of the mixture packet Pav as a time stamp value, and transmits the packet Pav to the sink device, and
• wherein the sink device receives the mixture packet Pav, extracts the time stamp value Csource(t) from the header part of the mixture packet Pav, generates a fixed reference clock CLKref based on the time stamp value Csource(t) using a first PLL circuit, generates the clock CLKpixel for the pixel data of the source device based on the reference clock CLKref using a second PLL circuit, and generates the reference clock CLKaudio for the audio data of the source device based on the reference clock CLKref2 using a third PLL circuit.

A communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a first transmitting counter, counts a reference clock CLKaudio for audio data using a second transmitting counter, adds a counted value Csource 1(t) of the first transmitting counter and a counted value Csource2(t) of the second transmitting counter at a timing of transmitting a mixture packet Pav including video data and audio data to the sink device, to a header part of the mixture packet Pav as time stamp values, and transmits the packet Pav to the sink device, and
• wherein the sink device receives the mixture packet Pav, extracts the time stamp value Csource 1(t) and the time stamp value Csource2(t) from the header part of the mixture packet Pay, generates a fixed reference clock CLKref1 based on the time stamp value Csource 1(t) using a first PLL circuit, generates the clock CLKpixel for the pixel data of the source device based on the reference clock CLKref1 using a second PLL circuit, generates a fixed reference clock CLKref2 based on the time stamp value Csource2(t) using a fourth PLL circuit, and generates the reference clock CLKaudio for the audio data of the source device based on the reference clock CLKref2 using a third PLL circuit.

A clock synchronization method for a communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting a video packet Pvideo to the sink device, to a header part of the video packet Pvideo as a time stamp value, and transmits the video packet Pvideo to the sink device, and
• wherein the sink device receives the video packet Pvideo, extracts the time stamp value Csource(t) from the header part of the video packet Pvideo, generates a fixed reference clock CLKref with a predetermined first frequency division parameter based on the counted value Csource(t) of the transmitting counter using a first PLL circuit, and generates the clock CLKpixel for the pixel data of the source device with a predetermined second frequency division parameter based on the reference clock CLKref using a second PLL circuit.

A clock synchronization method for a communication system comprising a source device and a sink device connected to each other via a Communication line,

• wherein the source device counts a clock CLKaudio for audio data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting an audio packet Paudio to the sink device, to a header part of the audio packet Pvideo as a time stamp value, and transmits the audio packet Paudio to the sink device, and
• wherein the sink device receives the audio packet Paudio, extracts the time stamp value Csource(t) from the header part of the audio packet Paudio, generates a fixed reference clock CLKref based on the time stamp value Csource(t) using a first PLL circuit, and generates the clock CLKaudio for the audio data of the source device based on the reference clock CLKref using a second PLL circuit.

A clock synchronization method for a communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting a mixture packet Pav including video data and audio data to the sink device, to a header part of the mixture packet Pav as a time stamp value, and transmits the packet Pav to the sink device, and
• wherein the sink device receives the mixture packet Pav, extracts the time stamp value Csource(t) from the header part of the mixture packet Pav, generates a fixed reference clock CLKref based on the time stamp value Csource(t) using a first PLL circuit, generates the clock CLKpixel for the pixel data of the source device based on the reference clock CLKref using a second PLL circuit, and generates the reference clock CLKaudio for the audio data of the source device based on the reference clock CLKref2 using a third PLL circuit.

A clock synchronization method for a communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a first transmitting counter, counts a reference clock CLKaudio for audio data using a second transmitting counter, adds a counted value Csource 1(t) of the first transmitting counter and a counted value Csource2(t) of the second transmitting counter at a timing of transmitting a mixture packet Pav including video data and audio data to the sink device, to a header part of the mixture packet Pav as time stamp values, and transmits the packet Pav to the sink device, and
• wherein the sink device receives the mixture packet Pav, extracts the time stamp value Csource1(t) and the time stamp value Csource2(t) from the header part of the mixture packet Pay, generates a fixed reference clock CLKref1 based on the time stamp value Csource1(t) using a first PLL circuit, generates the clock CLKpixel for the pixel data of the source device based on the reference clock CLKref1 using a second PLL circuit, generates a fixed reference clock CLKref2 based on the time stamp value Csource2(t) using a fourth PLL circuit, and generates the reference clock CLKaudio for the audio data of the source device based on the reference clock CLKref2 using a third PLL circuit.

A communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting a video packet Pvideo to the sink device, to a header part of the video packet Pvideo as a time stamp value, and transmits the video packet Pvideo to the sink device, and
• wherein the sink device receives the video packet Pvideo, extracts the time stamp value Csource(t) from the header part of the video packet Pvideo, generates a fixed reference clock CLKref based on the counted value Csource(t) of the transmitting counter and the clock CLKpixel for the pixel data generated by a second PLL circuit using a first PLL circuit, and generates the clock CLKpixel for the pixel data of the source device with a predetermined second frequency division parameter based on the reference clock CLKref using the second PLL circuit.

A clock synchronization method for a communication system comprising a source device and a sink device connected to each other via a communication line,

• wherein the source device counts a clock CLKpixel for pixel data using a transmitting counter, adds a counted value Csource(t) of the transmitting counter at a timing of transmitting a video packet Pvideo to the sink device, to a header part of the video packet Pvideo as a time stamp value, and transmits the video packet Pvideo to the sink device, and
• wherein the sink device receives the video packet Pvideo, extracts the time stamp value Csource(t) from the header part of the video packet Pvideo, generates a fixed reference clock CLKref based on the counted value Csource(t) of the transmitting counter and the clock CLKpixel for the pixel data generated by a second PLL circuit using a first PLL circuit, and generates the clock CLKpixel for the pixel data of the source device with a predetermined second frequency division parameter based on the reference clock CLKref using the second PLL circuit.