JP2008107397A - Transmission and reception system of hdmi transmission system and its related technique - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent voice disturbance caused by change of a stream data in a high definition multimedia interface (HDMI) transmission system. <P>SOLUTION: A voice change period information transmission means 13 transmits voice change period information Ax for controlling a period before and after changing of a data category, which is asserted in timing before a type of a voice stream data AD is changed, and which is negated after a predetermined period later than the timing that the category of the voice stream data is changed. A voice type information receiving means 32 receives a voice type information Ac for indicating a type of the voice stream data AD, and a voice change period information receiving means 33 receives the voice change period information Ax. A reproduction speed variable reproducing means 51a performs reproduction after converting reproduction speed of the received voice stream data AD, when the voice change period information Ax is being asserted. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a transmission / reception system of HDMI (High Definition Multimedia Interface) that handles a plurality of types of stream data in the HDMI transmission system for audio or video and related technology, and more specifically, a transmission device, a reception device, a transmission method, and a reception method The present invention relates to a technique for suppressing quality deterioration of audio output and video output when the type of stream data is changed regardless of a transmission / reception method.

  The HDMI transmission system transmission / reception system includes a video signal / audio signal transmission device (source side), a video signal / audio signal reception device (sink side), and an HDMI cable connecting the transmission device and the reception device. Has been. The HDMI cable is defined by the HDMI standard. The video signal is transmitted as video stream data (VIDEO SOURCE) and video type information (AVIInfoFrame) for identifying the type of the video signal. The audio signal is transmitted as audio stream data (AUDIO SOURCE) and audio type information (AudioInfoFrame) for identifying the type of the audio signal.

  There are several types of video signals, and representative examples include RGB and YCbCr. For example, when the video signal is switched from RGB to YCbCr, the transmission device changes the video stream data from RGB to YCbCr, and transmits video type information in which the video signal type is YCbCr, to the reception device. The receiving device receives the video type information through the HDMI cable, and processes the video stream data as YCbCr, thereby switching the video signal.

There are several types of audio signals, and representative examples include 44.1 kHz / DTS and 48 kHz / PCM. For example, when the audio signal is switched from 48 kHz / PCM to 44.1 kHz / DTS, the transmission apparatus changes the audio stream data from 48 kHz / PCM to 44.1 kHz / DTS, and the audio signal type is 44.1 kHz / DTS. The type information is transmitted to the receiving device. The receiving device receives the audio type information through the HDMI cable, and processes the audio stream data as 44.1 kHz / DTS, thereby switching the audio signal.
Japanese Patent Laying-Open No. 2005-323182 (page 5-8, FIG. 1-5)

  By the way, the HDMI standard presupposes that separate information such as video and audio stream data and video and audio type information can be transmitted and received simultaneously. No assumption is made if one of the information is delayed, and there is no function to detect that one of the information is missing, and the receiving device accurately detects the period during which one of the information is missing. I can't.

  If there is a time lag between the timing when the audio stream data changes from 48 kHz / PCM to 44.1 kHz / DTS and the reception of the audio type information of the receiving device, the receiving device erroneously changes the audio stream data 44.1 kHz / DTS to 48 kHz. / PCM is processed, and voice quality deteriorates due to noise mixing.

  FIG. 21 is a timing chart showing the operation when switching audio stream data in the prior art.

  In the period F1, the transmission device and the reception device transmit and receive the audio stream data AD at 48 kHz / PCM. In the transmitting device, the audio stream data AD and the audio type information Ac match, and also in the receiving device, the audio stream data AD and the audio type information Ac match.

  In the period F2, the audio stream data AD of the transmission device is switched to 44.1 kHz / DTS, and the audio type information Ac is also switched to 44.1 kHz / DTS. However, in the receiving apparatus, both the audio stream data AD and the audio type information Ac remain at 48 kHz / PCM.

  In the period F3, the transmission device is the same as the period F2. In the receiving apparatus, the audio stream data AD is switched to 44.1 kHz / DTS, but the audio type information Ac remains 48 kHz / PCM. This is because the audio stream data AD and the audio type information Ac are transmitted and received asynchronously. The audio stream data AD has arrived at the receiving device, but the audio type information Ac has not yet reached the receiving device. This period F3 is a speech format mismatch section Tz.

  In the period F4, the transmission device is the same as the period F3. In the receiving apparatus, the audio type information Ac is also switched to 44.1 kHz / DTS, which matches 44.1 kHz / DTS of the audio stream data AD.

  In the above, in the audio format mismatch section Tz, the audio stream data AD and the audio type information Ac do not match, so that the audio stream data AD is erroneously reproduced. That is, the audio stream data AD of 44.1 kHz / DTS is processed as 48 kHz / PCM. As a result, during this time lag, the audio signal of the receiving device becomes abnormal and the audio is disturbed.

  The above description is about audio stream data, but video stream data also has the same problem as shown in FIG.

  The present invention has been created in view of such circumstances, and in the HDMI transmission system, it is possible to suppress deterioration in quality of audio output and video output when the type of stream data is changed. It is aimed.

  The present invention takes the following means in order to solve the above problems.

  (1) The audio HDMI transmission system transmission apparatus SA according to the present invention shown in FIG. 1 includes an audio stream data transmission means 11 for transmitting a plurality of types of audio stream data AD in the HDMI transmission system, and an audio stream data transmission means 11. Assert at a timing before the timing at which the type of the audio stream data AD transmitted by the audio stream data transmitting unit 11 is switched, and the audio type information transmitting unit 12 that transmits the audio type information Ac indicating the type of the audio stream data AD to be transmitted. Voice switching period information transmitting means 13 for transmitting voice switching period information Ax that is negated after a lapse of a predetermined time from the switching timing of the type of the audio stream data AD and controls the period before and after the switching of the data type. I have.

  (2) The audio HDMI transmission system receiver RA according to the present invention shown in FIG. 1 includes an audio stream data receiving unit 31 for receiving a plurality of types of audio stream data AD of the HDMI transmission system, and an audio stream data receiving unit 31. The audio type information receiving means 32 for receiving the audio type information Ac indicating the type of the audio stream data AD to be received, and the audio switching period information Ax transmitted from the transmitting device SA, the audio stream transmitted by the transmitting device SA An audio switching period that is asserted at a timing prior to the timing at which the type of data AD is switched, negated after a predetermined time has elapsed from the timing at which the type of audio stream data AD is switched, and controls a period before and after the switching of the data type Voice switching period information receiving means for receiving information Ax 3 and the audio switching period information receiving unit 33 receives the audio switching period information Ax in a negated state, the audio type information receiving unit 32 receives the audio stream data AD received by the audio stream data receiving unit 31. Playback is performed at a playback speed corresponding to the audio type information Ac to be performed, and when the audio switching period information Ax is in an asserted state, playback speed conversion is performed after performing playback speed conversion on the audio stream data AD. Means 51a.

  (3) The audio HDMI transmission system receiver RA ′ according to the present invention shown in FIG. 2 includes an audio stream data receiving means 31 for receiving a plurality of types of audio stream data AD of the HDMI transmission system, and an audio stream data receiving means 31. The voice type information receiving means 32 for receiving the voice type information Ac indicating the type of the audio stream data AD received by the voice, and the voice switching period information Ax transmitted from the transmission device SA, the voice transmitted by the transmission device SA Audio switching that is asserted at a timing prior to the timing of switching the type of stream data AD and negated after a lapse of a predetermined time from the switching timing of the type of audio stream data AD to control a period before and after the switching of the data type Voice switching period information receiver who receives period information Ax 33 and the audio switching period information receiving unit 33 receives the audio switching period information Ax in a negated state, the audio type information receiving unit 32 receives the audio stream data AD received by the audio stream data receiving unit 31. And reproduction means 51b with mute processing for performing mute processing on the audio stream data AD when reproduction is performed at a reproduction speed corresponding to the audio type information Ac to be performed and the audio switching period information Ax is in an asserted state. .

  (4) As shown in FIG. 1 or FIG. 2, the audio HDMI transmission method transmission device SA and the audio HDMI transmission method reception device RA or RA ′ constitute an audio HDMI transmission method transmission / reception system. Yes.

  (5) The HDMI transmission method transmission method according to the present invention indicates an audio stream data transmission step for transmitting a plurality of types of audio stream data AD by the HDMI transmission method, and a type of the audio stream data AD to be transmitted in the audio stream data transmission step. The audio type information transmission step for transmitting the audio type information Ac and the timing at which the type of the audio stream data AD to be transmitted is asserted at a timing before the timing at which the type of the audio stream data AD to be transmitted is switched in the audio stream data transmission step. And a voice switching period information Ax transmission step that transmits voice switching period information Ax that is negated after the elapse of a predetermined time and controls a period before and after the switching of the data type.

  (6) The HDMI transmission method receiving method according to the present invention indicates an audio stream data receiving step for receiving a plurality of types of audio stream data AD of the HDMI transmission method, and a type of the audio stream data AD received in the audio stream data receiving step. The voice type information receiving step for receiving the voice type information Ac and the voice switching period information Ax transmitted from the transmission device SA before the timing at which the type of the audio stream data AD transmitted by the transmission device SA is switched. A voice switching period information receiving step that receives voice switching period information Ax that is asserted at timing and is negated after a lapse of a predetermined time from the switching timing of the type of the audio stream data AD and controls the period before and after the switching of the data type. And voice switching period information receiving step When the received audio switching period information Ax is in a negated state, the audio stream data AD received in the audio stream data receiving step is reproduced at a reproduction speed corresponding to the audio type information Ac received in the audio type information receiving step. When reproduction is performed and the audio switching period information Ax is in an asserted state, a reproduction speed variable reproduction step is performed in which reproduction is performed after performing a reproduction speed conversion on the audio stream data AD.

  (7) The HDMI transmission system reception method according to the present invention indicates an audio stream data reception process for receiving a plurality of types of audio stream data AD of the HDMI transmission system, and a type of the audio stream data AD received in the audio stream data reception process. The voice type information receiving step for receiving the voice type information Ac and the voice switching period information Ax transmitted from the transmission device SA before the timing at which the type of the audio stream data AD transmitted by the transmission device SA is switched. A voice switching period information receiving step that receives voice switching period information Ax that is asserted at timing and is negated after a lapse of a predetermined time from the switching timing of the type of the audio stream data AD and controls the period before and after the switching of the data type. And voice switching period information receiving step When the received audio switching period information Ax is in a negated state, the audio stream data AD received in the audio stream data receiving step is reproduced at a reproduction speed corresponding to the audio type information Ac received in the audio type information receiving step. When reproduction is performed and the audio switching period information Ax is in the asserted state, a reproduction process with mute processing for performing mute processing on the audio stream data AD is included.

  (8) The HDMI transmission method transmission / reception method according to the present invention is a combination of the HDMI transmission method transmission method (5) and the HDMI transmission method reception method (6) or (7).

  With the above configuration, when the type of audio stream data is changed in the transmission device, the audio stream data is within the audio format mismatch interval that is expected to be inconsistent between the audio stream data and the audio type information in the reception device. In this process, playback speed conversion is performed before playback or mute processing is performed, so that it is possible to prevent audio noise and improve the quality of audio output.

  The above description relates to a transmission device, a reception device, a transmission / reception system, a transmission method, a reception method, and a transmission / reception method for an audio HDMI transmission method. Hereinafter, a transmission device, a reception device, and a transmission / reception method for a video HDMI transmission method are described below. The system, transmission method, reception method, and transmission / reception method will be described.

  (9) The video HDMI transmission method transmitter SV for video according to the present invention shown in FIG. 3 includes a video stream data transmission unit 21 for transmitting a plurality of types of video stream data VD by the HDMI transmission method, and a video stream data transmission unit 21. Asserted at a timing before the switching timing of the video type information transmitting means 22 for transmitting the video type information Vc indicating the type of the video stream data VD to be transmitted and the type of the video stream data VD transmitted by the video stream data transmitting means 21 And a video switching period information transmitting unit 23 that transmits video switching period information Vx that is negated after a predetermined time from the switching timing of the type of the video stream data VD and controls the period before and after the switching of the data type. It is a thing.

  (10) The video transmission apparatus RV for video transmission RV according to the present invention shown in FIG. 3 includes a video stream data reception unit 41 for receiving a plurality of types of video stream data VD of the HDMI transmission system, and a video stream data reception unit 41. Video type information receiving means 42 for receiving video type information Vc indicating the type of video stream data VD to be received, and video switching period information Vx transmitted from the transmission device SV, the video stream transmitted by the transmission device SV A video switching period that is asserted at a timing prior to the timing at which the type of data VD is switched and negated after a predetermined time has elapsed from the timing at which the type of video stream data VD is switched to control a period before and after the switching of the data type Video switching period information receiver who receives information Vx 43 and when the video switching period information Vx received by the video switching period information receiving unit 43 is in a negated state, the video type information receiving unit 42 receives the video stream data VD received by the video stream data receiving unit 41. Playback is performed at a playback speed corresponding to the video type information Vc to be performed, and when the video switching period information Vx is in an asserted state, the playback is performed after the playback speed conversion is performed on the video stream data VD. And means 61a.

  (11) The video transmission apparatus RV ′ for video according to the present invention shown in FIG. 4 includes a video stream data receiving means 41 for receiving a plurality of types of video stream data VD of the HDMI transmission system, and a video stream data receiving means 41. The video type information receiving means 42 for receiving the video type information Vc indicating the type of the video stream data VD received in the video, and the video switching period information Vx transmitted from the transmission device SV, the video transmitted by the transmission device SV. Video switching that is asserted at a timing before the timing of switching the type of the stream data VD and negated after a lapse of a predetermined time from the switching timing of the type of the video stream data VD to control the period before and after the switching of the data type Video switching period information reception for receiving period information Vx When the video switching period information Vx received by the stage 43 and the video switching period information receiving means 43 is in a negated state, the video type information receiving means 42 receives the video stream data VD received by the video stream data receiving means 41. Reproduction means 61b with mute processing is provided for performing reproduction at a reproduction speed corresponding to the received video type information Vc and performing mute processing on the video stream data VD when the video switching period information Vx is in an asserted state. Is.

  (12) As shown in FIG. 3 or FIG. 4, a video HDMI transmission scheme transmission device SV and a video HDMI transmission scheme reception device RV or RV ′ constitute a video HDMI transmission scheme transmission / reception system. Yes.

  (13) The HDMI transmission system transmission method according to the present invention indicates a video stream data transmission process for transmitting a plurality of types of video stream data VD by the HDMI transmission system, and a type of video stream data VD transmitted in the video stream data transmission process. The video type information Vc transmission step for transmitting the video type information Vc is asserted at a timing before the timing at which the type of the video stream data VD to be transmitted in the video stream data transmission step is switched, and the type of the video stream data VD is switched. And a video switching period information transmitting step of transmitting video switching period information Vx that is negated after a predetermined time from timing and controls a period before and after the switching of the data type.

  (14) The HDMI transmission system reception method according to the present invention indicates a video stream data reception process for receiving a plurality of types of video stream data VD of the HDMI transmission system, and a type of video stream data VD received in the video stream data reception process. The video type information receiving step for receiving the video type information Vc, and the video switching period information Vx transmitted from the transmission device SV before the timing at which the type of the video stream data VD transmitted by the transmission device SV is switched. Video switching period information receiving step for receiving video switching period information Vx that is asserted at timing and negated after a predetermined time has elapsed from the switching timing of the type of the video stream data VD and controls the period before and after the switching of the data type And video switching period information receiver When the video switching period information Vx received in the video stream is in a negated state, the video stream data VD received in the video stream data receiving step is played back at a playback speed corresponding to the video type information Vc received in the video type information receiving step. And when the video switching period information Vx is in the asserted state, it includes a playback speed variable playback step of performing playback after converting the playback speed to the video stream data VD.

  (15) The HDMI transmission system reception method according to the present invention indicates a video stream data reception process for receiving a plurality of types of video stream data VD in the HDMI transmission system, and a type of video stream data VD received in the video stream data reception process. The video type information receiving step for receiving the video type information Vc, and the video switching period information Vx transmitted from the transmission device SV before the timing at which the type of the video stream data VD transmitted by the transmission device SV is switched. Video switching period information receiving step for receiving video switching period information Vx that is asserted at timing and negated after a predetermined time has elapsed from the switching timing of the type of the video stream data VD and controls the period before and after the switching of the data type And video switching period information receiver When the video switching period information Vx received in the video stream is in a negated state, the video stream data VD received in the video stream data receiving step is played back at a playback speed corresponding to the video type information Vc received in the video type information receiving step. And when the video switching period information Vx is in an asserted state, a playback process with a mute process for performing a mute process on the video stream data VD is included.

  (16) The HDMI transmission system transmission / reception method according to the present invention is a combination of the HDMI transmission system transmission method of (13) and the HDMI transmission system reception method of (14) or (15).

  With the above configuration, when the type of the video stream data is changed in the transmission device, the video stream data is within the audio format mismatch section in which the video stream data and the video type information are expected to be mismatched in the reception device. In this process, since the reproduction is performed after the reproduction speed is converted and the mute process is performed, it is possible to prevent the image noise and improve the quality of the image output.

  (17) The HDMI transmission method transmitter according to the present invention shown in FIG. 5 is a combination of the audio HDMI transmission method transmitter SA of (1) and the video HDMI transmission method transmitter SV of (9). It will be.

  (18) The video HDMI transmission system receiver according to the present invention shown in FIG. 5 or FIG. 6 includes the audio HDMI transmission system RA of (2) or (3) and (10) or (11). And the HDMI transmission system receivers RV and RV ′ for video.

  (19) As shown in FIGS. 5 and 6, the HDMI transmission system transmission / reception system according to the present invention includes the audio / video HDMI transmission system transmission device S of (17) and the audio / video HDMI transmission of (18). It consists of a combination with the system receiving device R.

  (20) The HDMI transmission method transmission method according to the present invention is a combination of the audio HDMI transmission method transmission method (5) and the video HDMI transmission method transmission method (13).

  (21) The HDMI transmission method reception method according to the present invention is a combination of the audio HDMI transmission method reception method (6) and the video HDMI transmission method reception method (14).

  (22) The HDMI transmission method reception method according to the present invention is a combination of the audio HDMI transmission method reception method (7) and the video HDMI transmission method reception method (15).

  (23) The HDMI transmission system transmission / reception method according to the present invention is a combination of the audio HDMI transmission system transmission / reception method (8) and the video HDMI transmission system transmission / reception method (16).

  By configuring as described above, when the type of the audio stream data or video stream data is changed in the transmission device, the audio stream data and the audio type information are expected to be inconsistent in the reception device, or In the audio format mismatch section where the video stream data and the video type information are expected to be inconsistent, playback or mute processing is performed after converting the playback speed in processing audio stream data or video stream data. It is possible to prevent audio noise and video noise and improve the quality of audio output and video output.

  According to the present invention, when the type of the audio / video stream data is changed in the transmission device, the audio / video stream data is recorded within the audio format mismatch section in which the stream data and the type information are expected to be mismatched in the reception device. In the processing, playback is performed after conversion of the playback speed, and mute processing is performed, so that audio noise and video noise can be prevented and the quality of audio output and video output can be improved.

  Such prevention of flickering of the HDMI screen and prevention of audio noise can be realized only by software without changing the hardware configuration.

  Embodiments of an HDMI transmission system transmission / reception system according to the present invention will be described below in detail with reference to the drawings.

  FIG. 7 is a block diagram showing a configuration of a transmission apparatus in the HDMI transmission system transmission / reception system according to the embodiment of the present invention.

  The transmission device 70 includes an audio signal processing device 71 and a transmission unit (Tx) 75.

  The audio signal processing device 71 includes an audio signal generation device 72 that generates an audio signal S71 such as 44.1 kHz / DTS or 48 kHz / PCM, a CPU 73, and a timer 74. The audio signal S71 generated by the audio signal processing device 71 is converted into the CPU 73. Output via. Further, the CPU 73 detects the switching of the audio signal S71 and outputs it as the audio control signal S12. The timer 74 has a timer function controlled by the CPU 73.

  The transmission unit 75 includes an HDMI transmission processing device 76 conforming to the HDMI standard. The HDMI transmission processing device 76 converts the audio signal S71 into audio stream data AD (AUDIO SOURCE) of the HDMI standard in a state controlled by the audio control signal S12. The data is converted and output to the HDMI cable 80. Also, the audio control signal S12 is input to generate audio type information Ac indicating the type of the audio stream data AD, and is further asserted at a timing before the timing at which the type of the audio stream data AD is switched. The voice switching period information Ax that is negated after a lapse of a predetermined time from the AD type switching timing and controls the period before and after the data type switching is generated, and the audio stream data AD, the voice type information Ac, and the voice switching period information are generated. Ax is collectively output to the HDMI cable 80 as audio HDMI data HA. The HDMI cable 80 conforms to the HDMI standard. The HDMI transmission system transmission device SA shown in FIGS. 1 and 2 is configured in the HDMI transmission processing device 76.

  FIG. 8 is a block diagram showing a configuration of a receiving apparatus in the HDMI transmission system transmission / reception system according to the embodiment of the present invention.

  The receiving device 90 includes a receiving unit (Rx) 91 and an audio output device 93. The receiving unit 91 includes an HDMI reception processing device 92 that conforms to the HDMI standard. The audio output device 93 includes a CPU 94, an audio signal output device 95 and a timer 96.

  The HDMI reception processing device 92 converts the audio stream data AD input from the HDMI cable 80 into an audio signal S91 and outputs it to the CPU 94. Also, the HDMI reception processing device 92 outputs the audio type information Ac and the audio switching period information Ax input from the HDMI cable 80 as the audio control signal S92.

  In the audio output device 93, the CPU 94 receives the audio signal S91 and the audio control signal S92 from the HDMI reception processing device 92, and performs predetermined audio processing or mute processing (AUDIO MUTE) on the audio signal S91 based on the audio control signal S92. Is output to the audio signal output device 95. The timer 96 has a timer function controlled by the CPU 94. The HDMI transmission system receivers RA and RA ′ shown in FIG. 1 and FIG.

  FIG. 9 shows the contents of the audio HDMI data HA. The HDMI data HA is defined by the HDMI standard and includes audio stream data AD, audio type information Ac, and audio switching period information Ax. The comparison with the prior art of audio | voice classification information Ac in this Embodiment is shown. Here, in the audio type information Ac, RESERVED (reserved), which is unused in the prior art, is used as the audio switching period information Ax.

  Next, the operation of the HDMI transmission system transmission / reception system of the present embodiment configured as described above will be described.

  First, the operation for switching the type of the audio stream data AD performed by the transmission apparatus 70 will be described based on the flowchart of FIG.

  When the type of the audio signal S71 is changed in the audio signal processing device 71, the CPU 73 detects a change in the signal from the audio signal generation device 72 and starts the processing from step S1.

  First, in step S <b> 1, the audio switching period information Ax is turned on and transmitted to the receiving unit 91 together with the audio stream data AD and the audio type information Ac via the transmitting unit 75. The audio switching period information Ax is active low here.

  Next, in step S2, idling for one vertical period is performed. A timer 74 is used for this idling.

  Next, in step S3, the audio stream data AD is switched, and the audio type information Ac is also switched at the same time.

  Next, in step S4, idling is performed for three vertical periods.

  Next, in step S5, the voice switching period information Ax is turned OFF, and the voice type information Ac after switching is transmitted to the receiving unit 91 via the transmitting unit 75.

  The process of FIG. 10 will be supplementarily described in comparison with the timing chart of FIG. FIG. 13 is a timing chart for audio output processing (speech speed conversion processing) accompanied by reproduction speed conversion. Since it is the operation of the transmission device 70, the upper part of FIG. 13 is referred to.

  It is assumed that the audio stream data AD initially transmitted is 48 kHz / PCM. The voice type information Ac is also 48 kHz / PCM. The voice switching period information Ax is OFF.

  Step S1 for turning on the voice switching period information Ax corresponds to the timing T1. Step S2 for performing idling of one vertical period corresponds to timings T1 to T2. Step S3 for switching the audio stream data AD and simultaneously switching the audio type information Ac corresponds to the timing T3. By this switching, the audio stream data AD becomes 44.1 kHz / DTS, and the audio type information Ac also becomes 44.1 kHz / DTS. Step S4 for performing idling of three vertical periods corresponds to timings T3 to T6. Step S5 for turning off the voice switching period information Ax corresponds to the timing T6.

  In the transmission device 70, the audio stream data AD and the audio type information Ac always match. That is, when the audio stream data AD is 48 kHz / PCM, the audio type information Ac is 48 kHz / PCM, and when the audio stream data AD is 44.1 kHz / DTS, the audio type information Ac is also 44.1 kHz / DTS.

  Next, the operation of the receiving device 90 when the type of the audio stream data AD is switched will be described based on the flowchart of FIG.

  When the CPU 94 determines that the voice switching period information Ax received via the receiving unit 91 is ON, the CPU 94 starts processing from step S11.

  First, in step S11, when it is confirmed that the audio stream data AD is switched and the audio type information Ac is switched, the process proceeds to step S12.

  Next, in step S12, it is determined whether the voice switching period information Ax is OFF or ON. If it is OFF, the process proceeds to step S13, and the audio output process or the audio mute process with a predetermined reproduction speed conversion is canceled. If it is ON, the process proceeds to step S14, and an audio output process or an audio mute process with a predetermined reproduction speed conversion is performed.

  The audio output process accompanied by the reproduction speed conversion is performed according to the flowchart of FIG.

  In step S21, speech speed conversion (reproduction speed conversion) is started. In step S22, the timer 96 is used to perform idling for one vertical period, and the audio stream data AD for one vertical period is buffered. Next, in step S23, it waits for the voice switching period information Ax to be turned off. When the audio switching period information Ax is turned OFF, the process proceeds to step S24, and the audio stream data AD is effectively switched as a reproduction operation.

  The process of FIG. 10 will be supplementarily described in comparison with the timing chart of FIG. Since this is the operation of the receiving device 90, the lower part of FIG.

  It is assumed that the audio stream data AD received initially is 48 kHz / PCM. The voice type information Ac is also 48 kHz / PCM. The voice switching period information Ax is OFF.

  Judging that the voice switching period information Ax is ON as a condition for shifting to step S11 corresponds to the timing T2. With this as a trigger, speech speed conversion processing is executed on the audio stream data AD. This corresponds to the timings T2 to T7. Specifically, buffering of voice data in one vertical cycle is performed, and after the buffering is completed, voice data obtained by performing 0.2 × speed conversion processing on the buffered voice data is output.

  During this time, along with the switching of the audio stream data AD and the audio type information Ac of the transmitting device 70, the audio stream data AD is also switched in the receiving device 90, and the audio type information Ac is switched. However, the switching of the audio stream data AD from 48 kHz / PCM to 44.1 kHz / DTS is timing T4, and the switching of the audio type information Ac from 48 kHz / PCM to 44.1 kHz / DTS is timing T5. Thus, in the receiving device 90, a time lag occurs between the switching timing of the audio stream data AD and the switching timing of the audio type information Ac. T4 to T5 are voice format mismatch sections Tz.

  Actually, in the receiving apparatus 90, a predetermined period between before and after the voice format mismatch section Tz is set in advance so as to be the ON period of the voice switching period information Ax. The cause of the switching of the audio stream data AD in the receiving device 90 at the timing T4 is the switching of the audio stream data AD at the timing T3 in the transmitting device 70. In the receiving apparatus 90, in order to start the audio output process with the reproduction speed conversion from the timing ahead of the timing T4 at which the audio stream data AD is switched, the audio switching period information Ax is turned ON at the timing T2. Yes. Since there are two vertical cycles from timing T4 to timing T2, in the transmission apparatus 70, the audio switching period information Ax is turned ON at timing T1 of two vertical cycles forward with respect to the timing T3 of switching of the audio stream data AD. Like to do. The cause of switching of the audio type information Ac in the receiving device 90 at the timing T5 is switching of the audio stream data AD at the timing T3 in the transmitting device 70. In the receiving device 90, the voice switching period information Ax is returned to OFF at timing T7 in order to continue the voice output process with the reproduction speed conversion until the timing behind the timing T5 when the voice type information Ac is switched. . From timing T5 to timing T7, there are two vertical cycles backward. In the transmission device 70, the voice type information Ac is returned to OFF at the timing T6 of three vertical cycles backward with respect to the timing T3 of switching the voice type information Ac. The reason why the vertical period is increased is that the audio format mismatch section Tz, which is a time lag, is taken into account.

  As described above, in the receiving device 90, assuming the audio format mismatch section Tz in which there is a difference between the switching timing of the audio stream data AD and the switching timing of the audio type information Ac, before and after the audio format mismatch section Tz. Using the audio switching period information Ax (corresponding to 5 vertical cycles) to indicate a fixed interval, this audio switching period information Ax is generated from the front of the switching timing of the audio stream data AD and the audio type information Ac by the transmitting device 70. The voice switching period information Ax is transmitted to the transmission device 70, and the transmission device 70 that has received the voice switching period information Ax uses the voice switching period information Ax to perform a voice output process or a voice mute process with a predetermined playback speed conversion. By outputting to the audio signal output device 95, the occurrence of audio disturbance in the reproduction of the receiving device 90 It is prevented.

  FIG. 14 shows an operation in substantially the same situation as FIG. 13, and also shows detailed data examples of the audio stream data AD, the audio type information Ac, and the audio switching period information Ax. This is for changing the audio stream data AD from 48 kHz / PCM to 44.1 kHz / DTS.

  In the period F1, the transmission device 70 and the reception device 90 perform transmission / reception with the audio format set to 48 kHz / PCM. The voice switching period information Ax is OFF.

  In the period F2, the transmission device 70 detects the switching of the audio stream data AD and turns on the audio switching period information Ax.

  In the period F3, the receiving device 90 receives ON of the voice switching period information Ax.

  In the period F4, the audio stream data AD of the transmission device 70 is switched from 48 kHz / PCM to 44.1 kHz / DTS, and the audio type information Ac is also switched to 44.1 kHz / DTS. However, in the receiving device 90, both the audio stream data AD and the audio type information Ac remain at 48 kHz / PCM.

  In the period F5, the transmission device 70 is the same as the period F4. In the receiving device 90, the audio stream data AD is switched to 44.1 kHz / DTS, but the audio type information Ac remains 48 kHz / PCM. This is because the audio stream data AD and the audio type information Ac are transmitted and received asynchronously. The audio stream data AD has reached the receiving device 90, but the audio type information Ac has not yet reached the receiving device 90. This period F5 is a speech format mismatch section Tz. Here, since the audio stream data AD and the audio type information Ac do not match, in the conventional control, an erroneous reproduction process is performed on the audio stream data AD.

  In the period F6, the receiving device 90 recognizes that the audio type information Ac has been switched from 48 kHz / PCM to 44.1 kHz / DTS.

  In the period F7, the audio switching period information Ax is returned to OFF in the transmission device 70.

  In period F8, the receiving device 90 recognizes that the audio switching period information Ax has been turned off, and cancels the audio output process or audio mute process that involves a predetermined playback speed conversion.

  As described above, audio disturbance can be prevented by performing audio output processing or audio mute processing with predetermined reproduction speed conversion when switching audio stream data AD of the HDMI transmission method.

  The HDMI transmission system transmission / reception system for video stream data can also be configured in the same manner as described above, as shown in FIGS. 15 to 20 may be understood by replacing the description of the audio stream data with the video stream data, and the description thereof will be omitted.

  The technology of the present invention is useful for preventing audio disturbance and screen disturbance when switching stream data in an HDMI transmission system transmission / reception system.

Block diagram showing the configuration of an audio transmission / reception system for audio transmission according to the present invention (part 1) Block diagram showing the configuration of an audio HDMI transmission system transmission / reception system according to the present invention (part 2) Block diagram showing the configuration of a video transmission / reception system for video transmission according to the present invention (part 1) Block diagram showing the configuration of a video transmission / reception system for video transmission according to the present invention (part 2) Block diagram showing the configuration of an audio / video HDMI transmission system transmission / reception system according to the present invention (part 1) Block diagram showing the configuration of an audio / video HDMI transmission system transmission / reception system according to the present invention (part 2) The block diagram which shows the structure of the transmitter in the HDMI transmission system transmission / reception system for audio | voices in embodiment of this invention The block diagram which shows the structure of the receiver in the HDMI transmission system transmission / reception system for audio | voices in embodiment of this invention HDMI audio data configuration diagram The flowchart which shows the operation | movement when switching the kind of audio | voice stream data performed with the transmission apparatus for audio | voices in embodiment of this invention. The flowchart which shows operation | movement when the kind of audio stream data is switched in the receiver for audio | voice in embodiment of this invention. The flowchart which shows the operation | movement of the audio | voice output process accompanying the reproduction speed conversion in embodiment of this invention. Timing chart showing operation of audio output processing (speech speed conversion processing) accompanied by reproduction speed conversion in the embodiment of the present invention Timing chart showing audio reproduction control together with a specific example of data in an embodiment of the present invention The block diagram which shows the structure of the transmitter in the HDMI transmission system transmission / reception system for images | videos in embodiment of this invention The block diagram which shows the structure of the receiver in the HDMI transmission system transmission / reception system for images | videos in embodiment of this invention HDMI video data configuration diagram The flowchart which shows the operation | movement at the time of switching the kind of video stream data performed with the transmitter for video in embodiment of this invention The flowchart which shows operation | movement when the kind of video stream data is switched in the receiver for video in embodiment of this invention. The timing chart which shows the reproduction control for images in the embodiment of the present invention together with a specific example of data Timing chart showing operation when switching audio stream data in the prior art Timing chart showing operation when switching video stream data in the prior art

Explanation of symbols

S HDMI transmission system transmitter R HDMI transmission system receiver SA Audio HDMI transmission system transmitter RA, RA 'Audio HDMI transmission system receiver SV Video HDMI transmission system transmitter RV, RV' Video HDMI Transmission system receiver AD Audio stream data Ac Audio type information Ax Audio switching period information HA Audio HDMI data HV Video HDMI data VD Video stream data Vc Video type information Vx Video switching period information Tz Audio format mismatch section 11 Audio stream Data transmission unit 12 Audio type information transmission unit 13 Audio switching period information transmission unit 21 Video stream data transmission unit 22 Video type information transmission unit 23 Video switching period information transmission unit 31 Audio stream data reception unit 32 Audio type information reception unit 33 Voice switching period information receiving means 41 Video stream data receiving means 42 Video type information receiving means 43 Video switching period information receiving means 51a Playback speed variable playback means 51b Playback means with mute processing 61a Playback speed variable playback means 61b Playback means with mute processing 70 Audio transmitter 71 Audio signal processor 72 Audio signal generator 73 CPU
74 Timer 75 Transmitter (Tx)
76 HDMI transmission processing device 80 HDMI cable 90 audio receiving device 91 receiving unit (Rx)
92 HDMI reception processing device 93 Audio output device 94 CPU
95 Audio signal output device 96 Timer 100 Video transmission device 101 Video signal processing device 102 Video signal generation device 103 CPU
104 Timer 105 Transmitter (Tx)
106 HDMI Transmission Processing Device 110 HDMI Cable 120 Receiving Device for Video 121 Receiving Unit (Rx)
122 HDMI reception processing device 123 Audio output device 124 CPU
125 Video signal output device 126 Timer

Claims (23)

Audio stream data transmission means for transmitting a plurality of types of audio stream data in an HDMI transmission system;
Audio type information transmitting means for transmitting audio type information indicating the type of the audio stream data transmitted by the audio stream data transmitting means;
Switching of the data type is asserted at a timing before the timing at which the type of the audio stream data transmitted by the audio stream data transmitting means is switched, and is negated after a predetermined time elapses from the switching timing of the type of the audio stream data. A transmission apparatus for HDMI transmission system, comprising: audio switching period information transmitting means for transmitting audio switching period information for controlling a period extending before and after. Audio stream data receiving means for receiving a plurality of types of audio stream data of the HDMI transmission method;
Audio type information receiving means for receiving audio type information indicating the type of the audio stream data received by the audio stream data receiving means;
Audio switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the audio stream data transmitted by the transmission device is switched, and before the timing at which the type of the audio stream data is switched Voice switching period information receiving means for receiving voice switching period information that is negated after the elapse of a predetermined time and controls the period before and after switching of the data type;
When the voice switching period information received by the voice switching period information receiving unit is in a negated state, the voice type information receiving unit receives the voice type data with respect to the voice stream data received by the voice stream data receiving unit. Reproduction speed variable reproduction means for performing reproduction at a reproduction speed corresponding to the type information and performing reproduction after performing reproduction speed conversion on the audio stream data when the audio switching period information is in an asserted state. Provided HDMI transmission system receiver. Audio stream data receiving means for receiving a plurality of types of audio stream data of the HDMI transmission method;
Audio type information receiving means for receiving audio type information indicating the type of the audio stream data received by the audio stream data receiving means;
Audio switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the audio stream data transmitted by the transmission device is switched, and before the timing at which the type of the audio stream data is switched Voice switching period information receiving means for receiving voice switching period information that is negated after the elapse of a predetermined time and controls the period before and after switching of the data type;
When the voice switching period information received by the voice switching period information receiving unit is in a negated state, the voice type information receiving unit receives the voice type data with respect to the voice stream data received by the voice stream data receiving unit. An HDMI transmission system receiving apparatus comprising: a reproduction means with a mute process for performing reproduction at a reproduction speed corresponding to the type information and performing a mute process on the audio stream data when the audio switching period information is in an asserted state .   An HDMI transmission method transmission / reception system comprising the HDMI transmission method transmission device according to claim 1 and the HDMI transmission method reception device according to claim 2 or 3. An audio stream data transmission step of transmitting a plurality of types of audio stream data by an HDMI transmission method;
An audio type information transmitting step for transmitting audio type information indicating the type of the audio stream data to be transmitted in the audio stream data transmitting step;
Switching of the data type is asserted at a timing before the timing at which the type of the audio stream data to be transmitted is switched in the audio stream data transmission step, and is negated after a predetermined time elapses from the switching timing of the type of the audio stream data. An audio transmission period information transmitting step for transmitting audio switching period information for controlling a period extending before and after the transmission method. An audio stream data receiving step of receiving a plurality of types of audio stream data of the HDMI transmission method;
An audio type information receiving step for receiving audio type information indicating the type of the audio stream data received in the audio stream data receiving step;
Audio switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the audio stream data transmitted by the transmission device is switched, and before the timing at which the type of the audio stream data is switched A voice switching period information receiving step for receiving voice switching period information that is negated after the elapse of a predetermined time and controls the period before and after the switching of the data type;
When the audio switching period information received in the audio switching period information receiving step is in a negated state, the audio received in the audio type information receiving step with respect to the audio stream data received in the audio stream data receiving step A playback speed variable playback step of performing playback at a playback speed corresponding to the type information and performing playback after converting the playback speed of the audio stream data when the audio switching period information is in an asserted state. Including HDMI transmission method reception method. An audio stream data receiving step of receiving a plurality of types of audio stream data of the HDMI transmission method;
An audio type information receiving step for receiving audio type information indicating the type of the audio stream data received in the audio stream data receiving step;
Audio switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the audio stream data transmitted by the transmission device is switched, and before the timing at which the type of the audio stream data is switched A voice switching period information receiving step for receiving voice switching period information that is negated after the elapse of a predetermined time and controls the period before and after the switching of the data type;
When the audio switching period information received in the audio switching period information receiving step is in a negated state, the audio received in the audio type information receiving step with respect to the audio stream data received in the audio stream data receiving step An HDMI transmission method receiving method including: a reproduction step with mute processing that performs reproduction at a reproduction speed corresponding to the type information and performs mute processing on the audio stream data when the audio switching period information is in an asserted state.   An HDMI transmission method transmission / reception method comprising a combination of the HDMI transmission method transmission method according to claim 5 and the HDMI transmission method reception method according to claim 6 or 7. Video stream data transmitting means for transmitting a plurality of types of video stream data in an HDMI transmission system;
Video type information transmitting means for transmitting video type information indicating the type of the video stream data transmitted by the video stream data transmitting means;
The video stream data transmission means is asserted at a timing prior to the switching timing of the video stream data type, and is negated after a predetermined time has elapsed since the switching timing of the video stream data type. An HDMI transmission system transmission device comprising: video switching period information transmitting means for transmitting video switching period information for controlling a period extending before and after the video. Video stream data receiving means for receiving a plurality of types of video stream data in the HDMI transmission system;
Video type information receiving means for receiving video type information indicating the type of the video stream data received by the video stream data receiving means;
Video switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the video stream data transmitted by the transmission device is switched, and before the timing at which the video stream data type is switched Video switching period information receiving means for receiving video switching period information that is negated after a predetermined time and controls the period before and after the switching of the data type;
The video type information receiving means receives the video stream data received by the video stream data receiving means when the video switching period information received by the video switching period information receiving means is in a negated state. Playback speed variable playback means for performing playback at a playback speed corresponding to the type information and performing playback after converting the playback speed of the video stream data when the video switching period information is in an asserted state. Provided HDMI transmission system receiver. Video stream data receiving means for receiving a plurality of types of video stream data in the HDMI transmission system;
Video type information receiving means for receiving video type information indicating the type of the video stream data received by the video stream data receiving means;
Video switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the video stream data transmitted by the transmission device is switched, and before the timing at which the video stream data type is switched Video switching period information receiving means for receiving video switching period information that is negated after a predetermined time and controls the period before and after the switching of the data type;
The video type information receiving means receives the video stream data received by the video stream data receiving means when the video switching period information received by the video switching period information receiving means is in a negated state. An HDMI transmission system receiver comprising: a playback unit with a mute process that performs playback at a playback speed corresponding to the type information and performs a mute process on the video stream data when the video switching period information is in an asserted state .   An HDMI transmission scheme transmission / reception system comprising the HDMI transmission scheme transmission device according to claim 9 and the HDMI transmission scheme reception device according to claim 10 or 11. A video stream data transmission step of transmitting a plurality of types of video stream data by an HDMI transmission method;
A video type information transmitting step for transmitting video type information indicating a type of the video stream data to be transmitted in the video stream data transmitting step;
The video stream data transmission step is asserted at a timing prior to the switching timing of the video stream data type to be transmitted, and is negated after a predetermined time has elapsed since the switching timing of the video stream data type. And a video switching period information transmitting step for transmitting video switching period information for controlling a period extending before and after the transmission method. A video stream data receiving step of receiving a plurality of types of video stream data of the HDMI transmission method;
A video type information receiving step for receiving video type information indicating a type of the video stream data received in the video stream data receiving step;
Video switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the video stream data transmitted by the transmission device is switched, and before the timing at which the video stream data type is switched Video switching period information receiving step for receiving video switching period information that is negated after a predetermined time and controls the period before and after the switching of the data type;
When the video switching period information received in the video switching period information receiving step is in a negated state, the video received in the video type information receiving step with respect to the video stream data received in the video stream data receiving step A playback speed variable playback step of performing playback after performing playback speed conversion on the video stream data when playback is performed at a playback speed corresponding to the type information and the video switching period information is in an asserted state. Including HDMI transmission method reception method. A video stream data receiving step of receiving a plurality of types of video stream data of the HDMI transmission method;
A video type information receiving step for receiving video type information indicating a type of the video stream data received in the video stream data receiving step;
Video switching period information transmitted from the transmission device, asserted at a timing before the timing at which the type of the video stream data transmitted by the transmission device is switched, and before the timing at which the video stream data type is switched Video switching period information receiving step for receiving video switching period information that is negated after a predetermined time and controls the period before and after the switching of the data type;
When the video switching period information received in the video switching period information receiving step is in a negated state, the video received in the video type information receiving step with respect to the video stream data received in the video stream data receiving step An HDMI transmission method reception method including: a reproduction step with mute processing for performing reproduction at a reproduction speed corresponding to the type information and performing mute processing on the video stream data when the video switching period information is in an asserted state.   An HDMI transmission method transmission / reception method comprising a combination of the HDMI transmission method transmission method according to claim 13 and the HDMI transmission method reception method according to claim 14 or 15.   An HDMI transmission method transmission device comprising a combination of the audio HDMI transmission method transmission device according to claim 1 and the video HDMI transmission method transmission device according to claim 9.   An HDMI transmission system receiver comprising a combination of the audio HDMI transmission system receiver according to claim 2 and the video HDMI transmission system receiver according to claim 10 or 11.   19. An HDMI transmission system transmission / reception system comprising a combination of the audio / video HDMI transmission system transmission apparatus according to claim 17 and the audio / video HDMI transmission system reception apparatus according to claim 18.   An HDMI transmission method transmission method comprising a combination of the audio HDMI transmission method transmission method according to claim 5 and the video HDMI transmission method transmission method according to claim 13.   15. An HDMI transmission method reception method comprising a combination of the audio HDMI transmission method reception method according to claim 6 and the video HDMI transmission method reception method according to claim 14.   An HDMI transmission system reception method comprising a combination of the audio HDMI transmission system reception method according to claim 7 and the video HDMI transmission system reception method according to claim 15.   An HDMI transmission method transmission / reception method comprising a combination of the audio HDMI transmission method transmission / reception method according to claim 8 and the video HDMI transmission method transmission / reception method according to claim 16.

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