JP2009038683A - Image signal output device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a change of color of an image, degradation due to transient and the like by changing over setting of a color gamut on a monitor side when a plurality of image signals different in color space specifications are mixed. <P>SOLUTION: An image signal of a first color space specification and an image signal of a second color space specification of a color gamut wider than that specified by the first color space specification are temporally changed over to each other, and supplied to a video graphic processor 12; the video graphic processor 12 converts the image signal of the first color space specification to a pseudo wide color gamut signal by expanding the color gamut thereof to the color gamut of the second color space specification in a pseudo manner, and transmits it to an HDMI Tx (transmitter) 14; and the HDMI Tx 14 transmits the pseudo wide color gamut signal, the image signal of the second color space specification, and color space information fixed to the second color space specification. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image signal output apparatus and method for processing and outputting a plurality of image signals (video signals) having different color space standards.

  Conventionally, in display and HDTV (High Definition TeleVision) broadcasting, sRGB (IEC (International Electrotechnical Commission) 61966-2-1) and ITU-R (International Telecommunication Union-Radiocommunication Sector) BT. The color space standardized in 709 is widely used, but in recent years, with the advent of wide color gamut panels, color representation of a wide color gamut exceeding sRGB has become possible on the receiver side.

  In other words, a display using a conventional CRT (cathode ray tube) can only display colors that are inside the color space covered by, for example, sRGB, and high-saturation colors that exist in nature must be viewed correctly through the display. I could not. However, with the recent display technology, displays with a wider color gamut have appeared, and typical displays that support a wide color gamut include liquid crystal television receivers that use LED (light emitting diode) backlights, etc. It has been known.

  As a video signal (image signal) standard suitable for such a wide color gamut display, a video signal specification having a wide color gamut while maintaining compatibility with conventional signals has been studied, and xvYCC has been standardized. This xvYCC is a standard issued by the International Electrotechnical Commission (IEC) as an international standard (IEC 61966-2-4), and is an ITU-R BT. The color space is expanded while ensuring compatibility with the 709 color gamut (equivalent to sRGB). According to this xvYCC, it is possible to express a color that cannot be expressed by the color space standard “ITU-R BT.709” (corresponding to sRGB in a still image) of the current moving image content.

  In the case of transmission using a wide color space such as this xvYCC, the color space of the sender and the receiver may be different, so it is recognized that the xvYCC signal is transmitted between the sender and the receiver and the correct display is made. Need to do. For this reason, for example, it is also possible to receive color space information together with a video signal from a source device using HDMI (High-Definition Multimedia Interface). From HDMI version 1.3, metadata and xvYCC A color space definition was added.

  That is, since only the SMPTE 170M / ITU601 or ITU709 color space has been defined in the AVI (Auxiliary Video Information) InfoFrame as the attribute data of the HDMI standard, there is a field for a new color space such as xvYCC. added. When an xvYCC signal is transmitted between devices compatible with HDMI version 1.3, the correct color gamut display (Gamut Mapping) can be realized by the receiver and the sender by complying with these standards.

  As a conventional technique, Patent Document 1 discloses a technique that makes it possible to obtain a desired color reproduction using a standard color space with an expanded color gamut.

JP 2006-180477 A

  By the way, when a wide color gamut signal defined by the standard xvYCC of a video signal having a wide color gamut as described above is transmitted on the HDMI, the connected display (display device such as a receiver) corresponds to xvYCC. In this case, the format stipulates that the color gamut identification flag and metadata of the signal transmitted to the HDMI AVI InfoFrame are written. An xvYCC-compatible display discriminates this signal and automatically performs color gamut setting on the display surface, thereby enabling optimum color reproduction. That is, when the conventional color gamut signal and the wide color gamut signal are switched, the display side or the monitor side switches the color gamut setting based on the AVI InfoFrame information. It is very difficult to match the change point and the switching point of the control signal of the AVI InfoFrame. Even if the change points are matched on the sender side, the timing may be shifted on the receiver side, and vice versa. If the actual signal and the color gamut setting timing on the monitor side are different, there is a problem that an image of an undesirable color is displayed for a moment due to the transient.

  The present invention has been proposed in view of such a conventional situation, and in the case where a plurality of image signals (video signals) having different color space standards are mixed, an image obtained by switching the setting of the color gamut on the monitor side. It is an object of the present invention to provide an image signal output apparatus and method that can prevent the color change of the image, deterioration due to transients, and the like.

  In order to solve the above-described problems, the present invention provides an image signal of the first color space standard and an image of the second color space standard having a wider color gamut than the color gamut defined by the first color space standard. An image signal output apparatus for processing and outputting a signal, wherein the color gamut is pseudo-expanded to the color gamut of the second color space standard with respect to the image signal of the first color space standard. A color gamut conversion processing means for converting to a color gamut signal; a transmission means for transmitting an image signal including the pseudo wide color gamut signal from the color gamut conversion processing means and color space information; and the first color space standard. When transmitting an image signal in which an image signal and the image signal of the second color space standard are mixed, the image signal of the first color space standard is transmitted to the second color space standard by the color gamut conversion processing means. A pseudo wide color gamut signal and the second color space which are pseudo extended to And color space information of case of the image signal and the second color space standard and having a control unit for controlling to transmit by the transmitting means.

  In order to solve the above-described problem, the present invention provides an image signal of the first color space standard and a second color space standard having a color gamut wider than the color gamut defined by the first color space standard. An image signal output method for processing and outputting the image signal of the first color space, wherein the color gamut is pseudo-expanded to the color gamut of the second color space standard for the image signal of the first color space standard A color gamut conversion processing step for converting to a pseudo wide color gamut signal, and an image signal and color space including a pseudo wide color gamut signal pseudo-expanded to the color gamut of the second color space standard by the color gamut conversion process And transmitting the information, and transmitting the first color when transmitting the image signal in which the image signal of the first color space standard and the image signal of the second color space standard are mixed. The image signal of the space standard is pseudo-expanded to the color gamut of the second color space standard, and the color of the second color space standard And controls to transmit together between information.

  Here, the image signal in which the image signal of the first color space standard and the image signal of the second color space standard are mixed is the image signal of the first color space standard and the second color space standard. It is mentioned that the image signal is temporally switched. In the color gamut conversion process, the level conversion gain of the color signal component of the image signal of the first color space standard is controlled independently in a range below a predetermined threshold of the signal level and a range above it. Thus, the color gamut may be expanded to the color gamut of the second color space standard in a pseudo manner, and a predetermined threshold value of the signal level for the color signal component of the image signal of the first color space standard. It is preferable to use the signal in the following range as it is and perform level conversion so that the signal in the range above a predetermined threshold is extended to the color gamut of the second color space standard.

  In the present invention, the image signal of the first color space standard is converted to the second color space standard for the image signal in which the image signal of the first color space standard and the image signal of the second color space standard are mixed. The color space information is fixed to that of the second color space standard and transmitted together with the image signal.

  According to the present invention, the image signal of the first color space standard and the image signal of the second color space standard are mixed, and the image signal of the first color space standard is the second color space standard. And a color fixed to the pseudo wide color gamut signal, the image signal of the second color space standard, and the color space information of the second color space standard. By transmitting spatial information, it is not necessary to switch the color gamut setting on the display side (monitor side) based on the transmitted color space information, and it is possible to prevent changes in the color of the video and deterioration due to transients. And an optimal color gamut can be obtained.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a playback system according to an embodiment of the present invention. In this reproduction system, a recording / reproduction apparatus 1 as an image signal output apparatus and a receiver 2 for displaying an image are connected via an HDMI (High-Definition Multimedia Interface) cable 3. The receiver 2 can display the image data of the first color space standard and the image data of the second color space standard having a wider color gamut than the color gamut defined by the first color space standard. In addition, it is possible to display the image data of the first color space standard in a pseudo color gamut with the image data of the second color space standard. Examples of the first color space standard include sRGB (IEC 61966-2-1), ITU-R BT. 709 and the like. Examples of the second color space standard include xvYCC.

  xvYCC is a standard issued by the International Electrotechnical Commission (IEC) as an international standard (IEC 61966-2-4), and is an ITU-R BT. The color space is expanded while ensuring compatibility with the 709 color gamut (equivalent to sRGB). According to this xvYCC, it is possible to express a color that cannot be expressed by the color space standard “ITU-R BT.709” (corresponding to sRGB in a still image) of the current moving image content.

  FIG. 2 is a schematic diagram when a color gamut of xvYCC is projected onto a plane. In FIG. 2, a color gamut a is an sRGB color gamut, and a color gamut b is a color gamut expanded by xvYCC. As shown in FIG. 2, in sRGB, only colors expressing R, G, and B as 0 to 1 have been used, whereas in xvYCC, negative values and colors exceeding 1 are defined. Therefore, for example, the receiver 2 performs processing for expanding the video content of the sRGB color gamut a to the color gamut b (hereinafter referred to as “color gamut expansion processing”) to faithfully reproduce the material feeling and stereoscopic effect of the object. If reproduced, the user can enjoy a color image with a wide color gamut.

  HDMI, which is the standard for the HDMI cable 3, is upwardly compatible with IEEE 1394, TMDS (Transition Minimized Differential Signaling) for the physical layer, HDCP (High-bandwidth Digital Content Protection) for signal encryption, and inter-device authentication EDID (Extended Display Identification Data) is used, and CEC (Consumer Electronics Control) is used for control system connection of the entire system. Also, the definition of metadata and xvYCC color space is added to HDMI version 1.3. Therefore, for example, if the image data is subjected to color gamut expansion processing based on the metadata received from the recording / reproducing apparatus 1 and its own color gamut information (color space information), more specifically, the image data is converted into image data. On the other hand, if color space conversion processing (Gamut Mapping Algorithm) between devices is performed, correct colors can be reproduced.

  Returning to FIG. 1, the configuration of the playback system will be described. A recording / playback apparatus 1 as an image signal output apparatus includes an MPEG (Moving Picture Expert Group) decoder 11, a video graphic processor 12, a host CPU (Central Processing Unit) 13, an HDMI Tx (transmitter) 14, and an HDMI. And a connector 15.

  The MPEG decoder 11 includes MPEG1, MPEG2, MPEG4, MPEG4-AVC / H. A video stream such as H.264 is decoded to generate a baseband signal.

  The video graphic processor 12 converts the baseband signal generated by the MPEG decoder 11 into a desired image frame size or synthesizes a plurality of baseband signals.

  The host CPU 13 controls the MPEG decoder 11 and the video graphic processor 12. For example, the MPEG decoder 11 is instructed to decode a desired video stream, and the video graphic processor 12 is instructed to generate a composite image using the decoded baseband signal, and to perform a pseudo expansion process of the color gamut. . Further, the color space standard of the processed image is determined, and the color space information is sent to the HDMI Tx14. The host CPU 13 communicates with the receiver 2 through a DDC (Display Data Channel) line of the HDMI cable 3.

  The HDMI Tx 14 includes a video / audio signal signal-processed by the video graphic processor 12, a color gamut identification flag indicating a color space standard as color space information sent from the host CPU 13, and meta information which is information associated with the color gamut. Attribute data such as data is converted into a TMDS signal and output to the HDMI connector 15. This attribute data can be transmitted using an AVI (Auxiliary Video Information) InfoFrame defined in the HDMI standard.

  The HDMI connector 15 is connected to the HDMI cable 3 and transmits a TMDS signal converted by the HDMI Tx 14 to the receiver 2.

  Next, the configuration of the receiver 2 will be described. The receiver 2 includes an HDMI connector 21, an HDMI Rx (receiver) 22, a host CPU 23, an extended display identification data read only memory (EDIDROM) 24, a video graphic processor 25, and a display device 26. Yes.

  The HDMI connector 21 is connected to the HDMI cable 3 and receives a TMDS signal.

  The HDMI Rx 22 acquires a video / audio signal and attribute data from the TMDS signal and sends the video signal to the video graphic processor 25.

  The host CPU 23 controls on / off of the color gamut expansion processing of the video graphic processor 25 based on the attribute data, for example. Specifically, for example, the color space information (color gamut identification flag) of the attribute data is ITU-R BT. In the case of 709, the color gamut expansion processing of the video graphic processor 25 is turned on, and when the color space information of the attribute data is xvYCC, the color gamut expansion processing of the video graphic processor 25 is turned off.

  The display information of the receiver 2 is stored in the EDIDROM 24. For example, the corresponding resolution information of the receiver 2 and color space information indicating the type of color gamut are written. Display information stored in the EDIDROM 24 is provided to the recording / reproducing apparatus 1 through a DDC (Display Data Channel) line of the HDMI cable 3.

  Next, FIG. 3 is a block diagram specifically showing the configuration of the recording / reproducing apparatus 1 as the image signal output apparatus of FIG. The recording / reproducing apparatus 1 includes a line input terminal 41, an analog tuner 42, a disk drive 43, a hard disk drive 44, an IEEE 1394 terminal 45, a digital tuner 46, and an input signal from the line input terminal 41 or the analog tuner 42. A selector 47 for selecting one of them, a video decoder 48 for decoding the video / audio signal from the selector 47, a baseband signal decoded by the video decoder 48, or an image composition by the video graphic processor 54, etc. A selector 49 that selects any one of the baseband signals subjected to signal processing, an MPEG encoder 50 that encodes the baseband signal from the selector 49, an HDV (High-Definition Video) processor 51, and a stream processor 52 And MPE Decoder 53a, and 53b, a video graphic processor 54, an HDMI TX55, a DAC 56, an HDMI connector 57, and a component terminal 58, a composite terminal 59, and a host CPU 60.

  Here, the MPEG decoders 53a and 53b, the video graphic processor 54, the HDMI Tx 55, the HDMI connector 57, and the host CPU 60 are respectively connected to the MPEG decoder 11, the video graphic processor 12, the HDMI Tx 14, the HDMI connector 15 shown in FIG. This corresponds to the host CPU 13.

  Next, a recording operation in the recording / reproducing apparatus 1 will be described. The video signal input from the line input terminal 41 and the video signal output from the analog tuner 42 are input to the video decoder 48 after a desired input is selected by the selector 47. The video decoder 48 A / D converts, for example, an input NTSC analog video signal, separates it into a luminance signal and a chroma signal, and performs a decoding process. The decoded baseband video signal is input to the selector 47 and the video graphic processor 54. After the selector 49 selects either the output from the video decoder 48 or the output from the video graphic processor 54, the selected baseband signal is input to the MPEG encoder 50. MPEG encoder 50 includes MPEG1, MPEG2, MPEG4, MPEG4-AVC / H. H.264 or other desired encoding is performed. The encoded stream is input to the stream processor 52. A stream is sent from the stream processor 52 to a disk drive 43 such as a BD (Blu-ray Disc (trademark)) or a DVD (Digital Versatile Disc), a hard disk drive 44, and the like, and is recorded on a desired medium.

  The stream input from the IEEE 1394 input terminal 45 is input to the stream processor 52 via the HDV processor 51, and the stream from the digital tuner 46 is also input to the stream processor 52. The stream input to the stream processor 52 is recorded on a desired medium such as a disk drive 43 or a hard disk drive 44 such as a BD or a DVD.

  The stream input to the stream processor 52 is subjected to processing such as extraction and parsing of a desired video stream by the stream processor 52, decoding by the MPEG decoder 53, and then passing through the video graphic processor 54 and the selector 49. To the MPEG encoder 50. MPEG encoder 50 includes MPEG1, MPEG2, MPEG4, MPEG4-AVC / H. H.264 or the like is performed, and the encoded stream is input to the stream processor 52. A stream is sent from the stream processor 52 to a disk drive 43 such as a BD or DVD, a hard disk drive 44, or the like, and recorded on a desired medium.

  Next, the reproducing operation in the recording / reproducing apparatus 1 will be described. A stream reproduced by the disk drive 43 or the hard disk drive 44 such as BD or DVD is input to the stream processor 52. The stream processor 52 extracts and parses a desired video stream, and sends it to the MPEG decoders 53a and 53b. The MPEG decoders 53a and 53b parse information (color space information) related to the color space attribute of the image data from the stream. The MPEG decoders 53a and 53b decode the image data. The baseband video signal decoded by the MPEG decoders 53a and 53b is input to the video graphic processor 54. In the video graphic processor 54, for example, conversion processing to a desired image frame size and various video signal processings are performed, and a graphics signal and the like are synthesized with the video signal, and then sent to the HDMI Tx 55. In HDMI Tx55, the input baseband signal is converted into a TMDS signal and output to the HDMI connector 57 together with a control signal. The output of the video graphic processor 54 is input to the DAC 56, and an analog component signal after D / A conversion is output to the component terminal 58, and an analog composite video signal (or Y / C separate) after D / A conversion is output. The video signal) is also output to the composite video terminal (or S terminal) 59.

  Here, the case of an image signal having a wide color gamut such as the xvYCC standard will be described. Along with a wide color gamut video signal, an identification flag for identifying the type of color gamut as color space information, and an accompanying color gamut. A disc such as a BD or DVD in which metadata or the like as information is recorded is reproduced by a disc drive 43.

  A stream including the reproduced wide color gamut video signal, identification flag, metadata, and the like is input to the stream processor 52. The stream processor 52 parses the stream and extracts the identification flag and metadata. The host CPU 60 acquires the identification flag and metadata. Since the identification flag and metadata indicating xvYCC are recorded as additional information of the elementary stream, synchronization with the video signal is always maintained.

  The stream including the wide color gamut video signal is decoded by the MPEG decoders 53a and 53b and then sent to the HDMI Tx 55 through the video graphic processor 54 as described in the above description of the reproduction system.

  Further, the host CPU 60 communicates with the receiver 2 through a DDC (Display Data Channel) line of the HDMI cable 3 connected to the HDMI connector 57, and via the HDMI Rx (receiver) 22 built in the receiver 2 and the host CPU 23. Thus, display information written in EDID (Extended Display Identification Data) ROM 24 is acquired. In the EDID ROM 24, color space information (colorimetry information) indicating the type of color gamut is written in addition to the resolution information corresponding to the receiver 2 and the like. Therefore, the host CPU 60 can determine whether or not the connected receiver 2 supports the wide color gamut video signal by acquiring the display information. When the receiver 2 connected by the HDMI cable 3 is compatible with the wide color gamut video signal, the host CPU 60 transmits the wide color gamut video signal when the color space acquired from the disk as an attribute of the video signal is transmitted. Information such as a color gamut identification flag and metadata can be set in the HDMI Tx55.

  The HDMI Tx 55 converts attribute data such as a color gamut identification flag and metadata into a TMDS signal together with the video / audio signal, and outputs the TMDS signal from the HDMI connector 57. The identification flag and metadata indicating the color gamut type can be transmitted using an AVI (Auxiliary Video Information) InfoFrame defined by the HDMI standard. For example, a color gamut identification flag as color space information is defined by Colorimetry or Extended Colorimetry in an AVI InfoFrame packet. Audio InfoFrame can be used as attribute data of the audio signal. Although attribute data such as a color gamut identification flag and metadata cannot be transmitted from the component terminal 58 and the composite video terminal (or S terminal) 59, an analog component signal of wide color gamut, an analog composite video signal (or Y) / C separate video signal).

  Next, the video graphic processor 54 of FIG. 3 will be described with reference to FIG. FIG. 4 shows a functional block diagram of the video graphics processor 54 when compositing images.

  In FIG. 4, the video graphic processor 54 includes a memory 301, synthesis processing units 302 a to 302 d, a graphic engine 306, and a JPEG engine 307. Here, the synthesis processing units 302 a to 302 d are prepared for each output format, and each include a scaler 308, a color expander 309, a blender 310, and a video encoder 311.

  The output of the video decoder 48 and the outputs of the MPEG decoders 53a and 53b are written in the video plane of the memory 301. In addition, the graphic engine 306 writes graphics data in the graphics plane of the memory 301. The JPEG engine 307 decodes the JPEG file and writes JPEG data to the video plane of the memory 301. The image data written in the memory 301 is read from each plane, scaled to a desired size by the scaler 308, and sent to the blender 310 via the color expander 309. The color expander 309 performs color gamut conversion processing for converting the image signal of the first color space standard into a pseudo wide color gamut signal obtained by artificially extending the color gamut to the color gamut of the second color space standard. Specifically, the sRGB color gamut is expanded to the xvYCC color gamut in a pseudo manner (color gamut expansion processing) and sent to the blender 310. The blender 310 synthesizes images read from each plane. The video encoder 311 performs timing generation, addition of a synchronization signal, and the like so as to obtain a desired output specification. The synthesis processing units 302b to 302d have a circuit configuration similar to that of the synthesis processing unit 302a, and perform processing according to the output form.

  Next, in the color expander 309, BT. 601 and BT. An example of an expansion process (color gamut expansion process) for converting a color gamut of 709 (first color space standard) into a color gamut of xvYCC (second color space standard) in a pseudo manner will be described.

  BT. 601 and BT. In 709, the value of the level of the chroma (Cr, Cb) signal is defined by 16-240. In xvYCC, in order to further expand the color gamut, a signal level of a value of 1-254 can be handled. Here, a conventional method for pseudo-changing a signal of a level to a wide color gamut will be described with reference to FIG.

  FIG. 5 is a diagram showing an example of level conversion at the time of expansion processing of the Cr signal and the Cb signal which are the chroma signals. 5A shows a Cr signal, FIG. 5B shows a Cb signal, and shows an output to the input of the color expander 309 for each of the Cr signal and the Cb signal. As described above, the Cr signal input to the color expander 309 is BT. 601 and BT. In 709, the level range of 16-240 is specified. When this is converted into a pseudo xvYCC signal, a signal in a predetermined level range, for example, a level range of 36-220 is passed as it is (with an amplification factor of 1), and a signal in the level range of 16-36 and a signal of 221-240 Each performs level conversion (level expansion with a constant amplification factor greater than 1) by linear processing, the level range of 16-36 expands to 1-36, and the level range of 221-240 expands to 221-254 Perform such conversion. As a result, a pseudo xvYCC signal is generated by further expanding the color signal having a relatively high saturation level of the original signal. Similarly, the Cb signal is expanded. For the pseudo xvYCC signal subjected to such color gamut expansion processing, an xvYCC flag (color space information of the second color space standard) can be used as the color space information, and the xvYCC signal and the pseudo xvYCC signal. Can be output and transmitted with the xvYCC flag fixed in the color space information.

  Although an example of the Cr and Cb signal expansion processing has been described with reference to FIG. 5, the same color gamut expansion may be performed on the RGB signals. Further, the level threshold may be changed, and the gain (amplification factor) of level conversion may be controlled independently between the threshold and the range above and below the threshold. Furthermore, the same effect can be obtained by performing non-linear processing for level conversion.

  Next, an example of the control operation of the color expander 309 and input / output signals will be described with reference to FIGS.

  The host CPU 60 in FIG. 6 detects whether or not the color space standard of the currently output video signal is xvYCC, and sends the result to the color expander 309 as a color expander ON / OFF signal. The color expander 309 performs ON / OFF of the expansion process according to the color expand ON / OFF signal of the host CPU 60. That is, when a video signal in which xvYCC and 709/601 signals are mixed is input as shown in FIG. 7A, expansion processing is turned on for the 709/601 signals and converted into pseudo xvYCC signals. Therefore, as shown in FIG. 7B, an output signal having a wide color gamut can always be obtained, and the color space information transmitted together with the video signal is wide as shown in FIG. The color gamut identification flag (xvYCC identification signal) indicating the color gamut can be fixed.

  Here, when xvYCC and 709/601 signals before decompression are mixed, conventionally, the AVI color space information of the HDMITx 116 must be changed according to the signal, but in this way always xvYCC or By sending the pseudo xvYCC signal, it becomes possible to send a certain color gamut identification flag (xvYCC identification signal).

  Since the constant color gamut identification flag (xvYCC identification signal) is fixedly sent on the receiver 2 side (monitor side) in FIG. Is no longer necessary, and it is possible to prevent a change in the color of the video or deterioration due to a transient.

  According to the embodiment of the present invention described above, when videos having different color space standards are mixed, a normal 709/601 signal is converted into a pseudo xvYCC signal, which is a problem in the related art. It is possible to prevent an undesirable image from being displayed due to the switching timing on the sender side. As described above, since the xvYCC flag as color space information added on the elementary stream is detected on the sending side, the switching timing between the xvYCC signal and the pseudo xvYCC can be accurately controlled internally. is there.

  In addition, in the case of analog transmission of component signals and the like, the flag stipulated by HDMI cannot be transmitted, so it is possible to obtain an optimal color gamut by always outputting xvYCC signals (including pseudo xvYCC) on the sending side. It is.

  In the embodiment of the present invention described above, the image signal of the first color space standard (for example, SMPTE 170M / ITU601 or ITU709) and the image signal of the second color space standard (for example, xvYCC) are switched over time. However, the present invention can also be applied to a case where a plurality of image signals of different color space standards are simultaneously mixed. In this case, when the first color space standard image signal is combined with the second color space standard image signal to generate one image signal, the first color space standard image signal is the first color signal. The color space information may be synthesized after being pseudo-expanded to the color gamut of the second color space standard, and the color space information may be fixed and output in the second color space standard.

  It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

It is a figure which shows the reproduction | regeneration system using the image signal output device used as embodiment of this invention. It is a schematic diagram at the time of projecting the color gamut of xvYCC on a plane. It is a block diagram which shows concretely the structure of the recording / reproducing apparatus as an image signal output device. It is a block diagram which shows the structure of a video graphic processor. It is a functional block diagram of a video graphic processor when combining images. It is a block diagram which shows roughly the structure for controlling a color expander. 6 is a timing chart for explaining an example of color space information for input / output signals and output signals of a color expander.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Recording / reproducing apparatus, 2 Receiver, 3 HDMI cable, 11 MPEG decoder, 12 Video graphic processor, 13 Host CPU, 14 HDMI Tx (transmitter), 15 HDMI connector, 21 HDMI connector, 22 HDMI Rx (receiver), 23 host CPU, 24 EDIDROM, 25 video graphic processor, 26 display device, 41 line input terminal, 42 analog tuner, 43 disk drive, 44 hard disk drive, 45 IEEE 1394 input terminal, 46 digital tuner, 47 selector, 48 video decoder , 49 selector, 50 encoder, 51 HDV processor, 52 stream processor, 5 Decoder, 54 video graphic processor, 60 a host CPU, 309 color expander

Claims (6)

An image signal output device that processes and outputs an image signal of a first color space standard and an image signal of a second color space standard having a color gamut wider than the color gamut defined by the first color space standard. There,
A color gamut conversion processing means for converting a color gamut into a pseudo wide color gamut signal pseudo-expanded to the color gamut of the second color space standard with respect to the image signal of the first color space standard;
A transmission means for transmitting the image signal including the pseudo wide color gamut signal from the color gamut conversion processing means and the color space information;
When transmitting an image signal in which the image signal of the first color space standard and the image signal of the second color space standard are mixed, the image signal of the first color space standard is converted to the color gamut conversion processing means. To pseudo-expand the color gamut of the second color space standard, the pseudo wide color gamut signal, the image signal of the second color space standard, and the color of the second color space standard. Control means for controlling to transmit spatial information by the transmission means. An image signal output device comprising:   The image signal in which the image signal of the first color space standard and the image signal of the second color space standard are mixed is the image signal of the first color space standard and the image signal of the second color space standard. 2. The image signal output apparatus according to claim 1, wherein and are switched over time.   The color gamut conversion processing means independently controls the level conversion gain of the color signal component of the image signal of the first color space standard in a range below a predetermined threshold of the signal level and a range above it. 2. The image signal output device according to claim 1, wherein the color gamut is extended to the color gamut of the second color space standard in a pseudo manner.   The color gamut conversion processing means uses a signal in a range below a predetermined threshold of the signal level as it is for the color signal component of the image signal of the first color space standard, and outputs a signal in a range above a predetermined threshold. 4. The image signal output apparatus according to claim 3, wherein the level conversion is performed so as to extend to the color gamut of the second color space standard.   2. The image signal output apparatus according to claim 1, wherein the transmission means transmits an identification flag indicating either the first color space standard or the second color space standard as the color space information. . An image signal output method for processing and outputting an image signal of a first color space standard and an image signal of a second color space standard having a color gamut wider than the color gamut defined by the first color space standard. There,
A color gamut conversion processing step for converting a color gamut into a pseudo wide color gamut signal pseudo-expanded to the color gamut of the second color space standard with respect to the image signal of the first color space standard;
A transmission step of transmitting an image signal including a pseudo wide color gamut signal pseudo-expanded to the color gamut of the second color space standard by the color gamut conversion process and color space information;
When transmitting an image signal in which the image signal of the first color space standard and the image signal of the second color space standard are mixed, the image signal of the first color space standard is transmitted to the second color space. A method of outputting an image signal, characterized in that control is performed so as to pseudo-expand to a standard color gamut and to transmit together with color space information of the second color space standard.

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