JP6435918B2 - Music playback device and program - Google Patents

Description

  The present invention relates to a technique for executing cross-fade processing of two videos in a music playback apparatus capable of playing back a sound represented by music information and playing a video represented by video information.

  2. Description of the Related Art Conventionally, in a music playback device that can play back video on a screen during playback of music, a sense of discomfort occurs when the video is suddenly switched. Therefore, taking the music reproducing device described in Patent Document 1 as an example, crossfade processing is executed in the music reproducing device. In the cross-fade process, the control unit executes a process of fading in the video to be displayed next, simultaneously with the process of fading out the video displayed when the video is replaced. In the music reproducing device described in Patent Document 1, in order to execute the cross-fade processing, the software decoder performs video information in a time zone during which video is being played, that is, a time zone in which the processing load of the software decoder is relatively low. Is decompressed (hereinafter referred to as “decode”), and the video information to be reproduced next is stored in the memory. Thereby, the music reproducing apparatus described in Patent Literature 1 can suppress the processing load of the software decoder during the cross-fade process.

JP 2010-54963 A

  However, although the music reproducing device described in Patent Document 1 can suppress the processing load of the CPU that executes the software decoder program, transmission of a bus that electrically connects each component such as the CPU and the memory. The limited capacity is not considered. Therefore, even if the software decoder resumes the decoding process when the decoded video information stored in the memory is less than the predetermined amount, the video information may not be decoded until the crossfade process is started due to insufficient bandwidth. is there.

  Furthermore, even if the conventional music reproducing apparatus has a very large bandwidth, lack of bandwidth becomes a problem as the resolution of the image is increased and the processing is diversified.

  Accordingly, the present invention has been made to solve the above-described problem, and a music reproducing apparatus that can effectively use a limited band and execute a cross-fade display process of a video represented by two pieces of video information. The purpose is to provide.

  The music playback device according to claim 1 is a controller that controls various processes for music playback, and first video information and second video information that represent video displayed on the display unit during music playback. Information is transmitted for processing by the first and second decoders, a memory having a temporary storage area for various processes controlled by the control unit, and the control unit, the first decoder, and the second decoder Various processes controlled by the control unit include: decoding of the first decoder and the second decoder; and displaying the video indicated by the first video information in a fade-out manner. Cross-fade display processing for fading-in display of the video to be displayed, and the control unit represents the transmission path capacity of the bus when controlling the cross-fade display processing A decoding start time of the second video information is determined based on a bandwidth, a bandwidth required for decoding the first video information, and a bandwidth used for the various processes other than the decoding of the two decoders. The second decoder starts decoding at the decoding start time before controlling the cross-fade display processing.

  According to a second aspect of the present invention, there is provided a music playback device for controlling various processes for music playback and first video information and second video information representing video displayed on a display unit during music playback. A first decoder and a second decoder, a memory including a temporary storage area for various processes controlled by the control unit, a bus connected to the control unit and the memory and transmitting information, The various processes controlled by the control unit include the decoding of the first decoder and the second decoder, the video indicated by the first video information being faded out, and the video indicated by the second video information being faded in. Cross-fade display processing, and when the control unit controls the cross-fade display processing, a total bandwidth indicating a transmission path capacity of the bus, and the first video A decoding start point of the second video information is determined based on a band necessary for decoding the information and a band used for the various processes other than the decoding of the two decoders, and the crossfade display process is performed. The second decoder is caused to start decoding at the decoding start time before control.

  The music reproducing apparatus according to claim 3, further comprising a bus monitor that measures a use band of the bus when the control unit controls the various processes, and the control unit is measured by the bus monitor from the total band. The surplus bandwidth is determined by subtracting the used bandwidth and the bandwidth necessary for decoding the first video information, and the decoding start time is determined according to the determined surplus bandwidth.

  The said control part which concerns on the music reproduction apparatus of Claim 4 calculates a decoding period by dividing the information amount of the said 2nd video information used for the said cross fade display process by the said surplus band, The said decoding start time Is a time point before the predetermined first time point from the start to the end of the crossfade display process by the length of the decoding period.

  The said various processes which concern on the music reproduction apparatus of Claim 5 include the reproduction | regeneration process of a music, and the display process of a telop, The priority which transmits the information for the said various processes is determined, A determination unit configured to determine an allocation band allocated for transmitting information according to a priority order, wherein the determination unit determines the allocation band in preference to a process having a higher priority, and the music of the various processes The priority for transmitting information for the reproduction processing and the display processing for the telop is determined to be higher than the priority for transmitting the information for the decoding of the first decoder and the decoding of the second decoder. At a predetermined second time point from the start to the end of the crossfade display process, the priority order for transmitting information for decoding by the second decoder is And determining as priority than the priority for transmitting information for decoding the first decoder.

  7. The control unit according to claim 6, wherein the priority for transmitting information for decoding by the second decoder is given priority over the priority for transmitting information for decoding by the first decoder. The decoding of the first video information indicating the video displayed at a predetermined third time point from the start to the end of the cross-fade display processing is determined by the determination unit as described above until the third time point. If not completed, the control unit displays the video according to the video information decoded at the time closest to the third time among the first video information decoded up to the third time. Thus, the cross-fade display process is controlled.

  According to the first, second, and seventh aspects of the invention, when the control unit controls the cross-fade display process, it is necessary for decoding the total bandwidth indicating the bus transmission path capacity and the first video information. Is determined based on the band to be used and the band used for various processes other than the decoding of both decoders, and the decoding start time is determined before the crossfade display process is controlled. The second decoder starts decoding. The decoding start point of the second video information is determined according to the surplus band, and the second decoder is caused to start decoding at the decoding start point before controlling the crossfade display processing. Thereby, it is possible to effectively use a limited band and to execute the cross-fade display processing of the video represented by the two video information.

  The control unit according to the music reproducing device according to claim 3 determines a surplus band according to the measurement result of the bus monitor 171 and determines a decoding start time according to the determined surplus band. Using the surplus bandwidth determined according to the measurement result of the bus monitor 171, the second decoder starts decoding from the decoding start time. This makes it possible to more effectively use the finite bandwidth and execute the cross-fade display processing of the video represented by the two video information.

  The decoding start time point according to the music reproducing device of claim 4 is a time point that is a length of the decoding period before a predetermined first time point from the start to the end of the cross-fade display process. The decoding of the second decoder is started from the predetermined first time point by the length of the decoding period using the determined surplus bandwidth. As a result, it is possible to more reliably execute the cross-fade display processing of the video represented by the two video information.

  6. The determination unit according to claim 5, wherein the determining unit prioritizes a process having a higher priority to determine an allocated band, and performs a music reproduction process and a telop display process among the various processes by a first decoder. , And prior to the decoding of the second decoder, the decoding of the second decoder is prioritized over the decoding of the first decoder at a predetermined second time point until the end of the cross-fade display processing. At the second time point, the decoding of the second decoder is given priority over the decoding of the first decoder. This makes it possible to reliably execute the cross-fade display processing of the video represented by the two video information even when the band available for the second decoder changes with time.

  The control unit according to the image processing device of claim 6, according to the video information of the first video information decoded up to the third time point, so that the video is displayed at a time point closest to the third time point, Controls the crossfade display process. When the decoding of the second decoder is prioritized, the first video information may use a decoded video before the third time point. Thereby, even when the decoding of the first video information is not in time, it is possible to reduce the sense of incongruity and to execute the crossfade display processing of the video represented by the two video information.

It is a block diagram of the music reproduction apparatus 1 in one Embodiment of this invention. 3 is a block diagram of a video control unit 150 of the music playback device 1. It is a flowchart figure which represents the process in CPU100 of the music reproduction apparatus 1. FIG. It is the schematic showing the process of the music reproduction apparatus 1 with a time change. It is the schematic showing the process of the conventional music reproduction apparatus with a time change.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the embodiment, the time point is determined based on the elapsed time from the start of music playback unless otherwise specified. In the description of the embodiment, the cross-fade display process is a process executed during a period represented by cross-fade display start time information and cross-fade display end time information, which will be described later, and means a process of displaying an image. . The cross-fade process is a process executed in a period represented by later-described decode start time information and cross-fade display end time information, and means a process of decoding the second video information and displaying the video. To do. Cross-fade display processing is executed during the cross-fade display processing period (S1) shown in the middle of FIG. Further, the cross-fade process is executed in the cross-fade process period (S2) shown in the middle of FIG.

[Electric configuration of music player]
FIG. 1 is a block diagram of a music playback device 1 according to an embodiment of the present invention. The music reproducing device 1 includes a control board 10 and an HDD 110. The control board 10 includes a CPU 100, a ROM 101, a RAM 102, a memory controller 103, an operation processing unit 120, an acoustic control unit 130, a first decoder 140, a second decoder 141, a video control unit 150, and a communication unit 160 as constituent elements. Each component described above is electrically connected by a bus 170.

  The CPU 100 controls various processes of the music playback device 1. The ROM 101 stores programs and applications executed by the CPU 100. The RAM 102 is a temporary storage area and temporarily stores information related to various processes. The memory controller 103 measures the storage state of the RAM 102 and determines the priority order of information for accessing the RAM 102 when executing various processes.

  The HDD 110 stores a plurality of music information, a plurality of lyrics telop information, and a plurality of video information in respective storage areas assigned thereto. The music information is information in the MIDI format representing the accompaniment sound of the music in the karaoke performance. The music information further includes switching time information, crossfade display start time information, and crossfade display end time information. The switching time point information represents the time point at which the video is switched. The cross-fade display start time point information represents a time point (time point TP3 shown in FIG. 4) at which the cross-fade display process before the time point indicated by the switching time point information is started. Further, the crossfade display end time point information represents a time point at which the crossfade display process ends (time point TP5 shown in FIG. 4). The lyrics telop information is information representing the lyrics and the song names displayed in synchronization with the reproduction of the accompaniment sound. The video information is information representing video displayed in synchronization with the reproduction of the accompaniment sound. Video information is encoded information. The music information, the lyrics telop information, and the video information each include music identification information. The video information includes a video that changes over time and decode position information that represents the elapsed time.

  When the user operates the operation unit 121, the operation processing unit 120 receives an operation signal indicating the operation from the operation unit 121. The operation processing unit 120 converts the operation signal into a control request for switching the operation of the CPU 100 and sends it to the CPU 100. For example, the operation unit 121 includes a switch or a touch panel. The operation unit 121 sends an operation signal indicating the position and the number of times of the switch pressed by the user or an operation signal indicating the position and the number of times of the touch panel touched by the user to the operation processing unit 120.

  Further, the operation processing unit 120 receives an operation signal received from the terminal 123 by the receiving unit 122 from the receiving unit 122. The operation processing unit 120 converts the operation signal into a control request for switching the operation of the CPU 100 and sends it to the CPU 100. For example, the terminal 123 is a user's portable terminal or a remote control device dedicated to the music playback device 1. The terminal 123 generates an operation signal and transmits the operation signal to the reception unit 122 when a switch or a touch panel included in the terminal 123 is operated by the user. The receiving unit 122 sends the operation signal received from the terminal 123 to the operation processing unit 120.

  The sound control unit 130 receives a reproduction command from the CPU 100. The reproduction command includes music information of the music to be reproduced and a reproduction start command. The sound control unit 130 generates a music signal that can be produced by the speaker 131 in accordance with the music information included in the reproduction command.

  When the sound control unit 130 receives the input sound information sent from the sound input unit 132, the sound control unit 130 provides effects such as amplification and echo. For example, the voice input unit 132 is a microphone. Sound input from the microphone is converted into input sound information and sent to the sound control unit 130. The input sound information is converted into an input sound signal by the sound control unit 130 with effects such as amplification and echo. The sound control unit 130 mixes the input sound signal and the music signal to generate a sound generation signal. The voice control unit 130 sends a sound generation signal to the speaker 131, and the speaker 131 generates a sound according to the sound generation signal.

  The first decoder 140 and the second decoder 141 decode video information. The first decoder 140 and the second decoder 141 receive a decode command from the CPU 100. The first decoder 140 and the second decoder 141 decode the destination address of the decoded data included in the decode command and the video information. When the decoding of the video information is finished, the decoded information representing the decoded information is sent to the video control unit 150 or the RAM 102. Hereinafter, a decode command sent to the first decoder 140 is referred to as a first decode command, video information decoded by the first decoder 140 is referred to as first video information, and information decoded by the first decoder 140 is referred to as first decode information. . Similarly, the decode command sent to the second decoder 141 is the second decode command, the video information decoded by the second decoder 141 is the second video information, the information decoded by the second decoder 141 is the second decode information, and so on. Called.

  As an example, the first decoder 140 is a main decoder, and decodes the first video information that fades out in the cross-fade process. The first decode command sent to the first decoder 140 includes the first video information and the address of the video control unit 150 that is the destination of the first decode information. In accordance with the first decoding command, the first decoder decodes the first video information and sends the first decoding information to the video control unit 150.

  The second decoder 141 is a sub decoder, and decodes the second video information to be faded in in the cross-fade process. The second decoding command sent to the second decoder 141 includes the second video information and the address of the RAM 102 that is the destination of the second decoding information. In accordance with the second decoding command, the second decoder decodes the second video information and sends the second decoding information to the RAM 102.

  The video control unit 150 receives the first decoding information, the second decoding information, and the lyrics telop information. The video control unit 150 D / A converts the first decode information and the second decode information. The video control unit 150 generates display information to be displayed on the monitor 151 by changing the output level of the first decode information and the second decode information by a fade circuit described later and further mixing with the lyrics telop information. To do. The configuration of the video control unit 150 will be described later.

  The communication unit 160 is connected to the Internet 200. The communication unit 160 can download music from a host server (not shown) via the Internet 200 and upload recorded data storing a user's performance state to a video site.

  The bus 170 is a common transmission path for each component to exchange information. The bus 170 includes a bus arbitration circuit and a bus monitor 171. The bus arbitration circuit arbitrates the right to send out information so that each component does not send information at the same time. The bus monitor 171 measures the used bandwidth used by the bus 170 and sends information representing the used bandwidth to the CPU 100. The band represents the amount of information (B / s) transmitted through the bus 170 per unit time and the amount of information (B / s) transmitted to the memory 102 or the like per unit time.

[Electrical Configuration of Video Control Unit 150]
FIG. 2 is a diagram for explaining the electrical configuration of the video controller 150. The video control unit 150 includes a DAC 1500, a first fade circuit 1501, a second fade circuit 1502, a first mixer 1503, and a second mixer 1504. The DAC 1500 converts the format of decoding information from digital to analog. The first fade circuit 1501 changes the output level of the first decode information. The second fade circuit 1502 changes the output level of the second decode information. The output level of the first fade circuit 1501 is changed according to the first fade circuit control command sent from the CPU 100. The output level of the second fade circuit 1502 is changed according to the second fade circuit control command sent from the CPU 100. The first mixer 1503 mixes the first decode information and the second decode information whose output level is changed. The second mixer 1504 mixes the first decode information and the second decode information mixed with the first mixer 1503 and the lyrics telop information. The display information mixed by the second mixer 1504 is sent to the monitor 151.

  The higher the output level of the first fade circuit 1501 and the second fade circuit 1502, the clearer the first decode information and the second decode information are displayed on the monitor 151. As the first fade circuit 1501 and the second fade circuit 1502 lower the output level, the first decode information and the second decode information are transmitted and displayed on the monitor 151. As an example, when the first fade circuit 1501 gradually lowers the output level of the first decode information from 100% according to the first fade circuit control information, the video of the first video information is faded out. The second fade circuit 1502 displays fade-in when the output level of the second decode information is gradually increased from 0% in accordance with the second fade circuit control information. When the fade-out display of the first decode information and the fade-in display of the second decode information are performed at the same time, the monitor 151 displays the video represented by the first decode information and the video represented by the second decode information according to the display information. To do.

[Operation and Action of Music Playback Device 1]
The operation and action of the music reproducing device 1 will be described with reference to FIG. FIG. 3 is a flowchart showing various processes executed by the CPU 100. The processing of the flowchart shown in FIG. 3 is started at the same time when the CPU 100 starts preparation for reproduction of the music to be reproduced next. In the following description, when executing the cross-fade process, information representing a video to be faded out is referred to as first video information, and a decoder that decodes the first video information is referred to as a first decoder 140. In addition, information representing a video to be faded-in display is referred to as second video information, and a decoder that decodes the second video information is referred to as a second decoder 141.

In step S100, decoding start time point information for starting decoding of the second video information is calculated. The decoding start time information is calculated by the following various information and mathematical expressions.

  The time point (time point TP2 shown in FIG. 4) represented by the decoding start time point information is from the reproduction start time point (time point TP1 shown in FIG. 4) before the time point (time point TP3 shown in FIG. 4) when the crossfade display process is started. It is determined by the elapsed time. From Equation 1, the time point indicated by the decoding start time point information (time point TP2 shown in FIG. 4) is the time point before the time point indicated by the switching time point information (time point TP4 shown in FIG. 4) by the length of the time period indicated by the decoding period information. Is calculated as From Equation 2, the decoding period information is calculated by dividing the information amount of the second video information to be faded in by the band obtained by subtracting the used band and the band necessary for decoding the first video information from the total band. . The usable bandwidth is determined by subtracting the used bandwidth from the total bandwidth representing the transmission path capacity of the bus 170 and calculating the decoding period. When a band necessary for decoding the first video information is subtracted from the usable band, an extra band that can be used for decoding the second video information at the time of calculating the decoding period information is obtained. When the information amount of the second video information to be faded in is divided by the surplus bandwidth, a period during which the process of decoding the second video information and transmitting it on the bus 170 can be calculated.

  Decoding start time information is calculated by the number of switching time information included in the music information. Specifically, when the process of step S100 is started, switching time point information is extracted. When the extraction of the switching time information is finished, based on the period represented by the decoding period information calculated by Equation 2 (time S3 shown in FIG. 4) and the time indicated by the switching time information (time TP4 shown in FIG. 4), Decoding start time information indicating the decoding start time (time TP2 shown in FIG. 4) is calculated. When the calculation of the decoding start time information is completed for all the switching time information included in the music information, the process proceeds to step S101.

  In step S101, a first decode command and a playback command are sent. Specifically, the elapsed time from the start of accompaniment sound reproduction and the elapsed time represented by the decode position information are synchronized. First, a reproduction command is sent to the sound control unit 130. The elapsed time from the reproduction start time of the accompaniment sound represented by the music information is measured, and a first decoding command synchronized with the elapsed time is sent to the first decoder 140. The first decode command synchronized with the elapsed time is a first decode command that includes decode position information indicating an elapsed time that matches the elapsed time of the accompaniment sound. In step S101, the accompaniment sound reproduction process represented by the music information is repeatedly controlled until the accompaniment sound has been reproduced. Further, the decoding of the first decoder 140 is repeatedly controlled until the crossfade process is completed. When the first decode command and the playback command are sent, the process proceeds to step S102.

  In step S102, it is determined whether or not the decoding start time indicated by the decoding start time information has come. If it is determined that the decoding start time has come, step S102 is YES, and the process proceeds to step S103. If it is determined that the decoding start time has not come, step S102 is NO, and the process of step S102 is continued.

  In step S103, the second decoding command is sent to the second decoder 141. The second decoder 141 starts decoding the second video information according to the decoding position information included in the second decoding command. The decoding start position is determined according to the crossfade display start time point information included in the music information. Furthermore, the priority order of the bands allocated to the processing of the second decoder 141 is determined to be the lowest order. The decoding of the second decoder controlled in step S103 is continued until the playback of the accompaniment sound is completed or the cross-fade process is executed again. The decoded second decode information is sent to the RAM 102 in accordance with the RAM 102 address included in the second decode command. When the second decode command is sent to second decoder 141, the process proceeds to step S104.

  In step S104, it is determined whether or not the crossfade display start time has come. If it is determined that it is the time indicated by the crossfade display start time information, step S104 is YES, and the process proceeds to step S105. If it is determined that it is not the time indicated by the crossfade display start time information, step S104 is NO and the process of step S104 is continued.

  In step S105, the first fade circuit control information is sent to the first fade circuit 1501, and the second fade circuit control information is sent to the second fade circuit 1502. Specifically, the first fade circuit control information is information that gradually lowers the output level of the first decode information output from the first fade circuit 1501 during the crossfade display period. As an example, the output level of the first decode information at the start of the crossfade display is 100%. The first fade circuit control information controls the first fade circuit 1501 so that the output level of the first decode information becomes 0% at the end of the cross fade display process. The cross-fade display period is a period for performing a cross-fade display process determined by cross-fade display start time information and cross-fade display end information associated with music information.

  The second fade circuit control information is information for gradually increasing the output level of the second decode information output from the second fade circuit 1502 during the crossfade display period. That is, if the output level of the second decode information at the start of the crossfade display is 0%, the second fade circuit control information is output so that the output level of the second decode information becomes 100% at the end of the crossfade display. The second fade circuit 1502 is controlled so as to gradually increase the level. The second decode information is stored in the previously decoded RAM 102 and is read from the RAM 102 when it is determined that the crossfade display start time has come. When the first fade circuit control information and the second fade circuit control information are sent to the first fade circuit 1501 and the second fade circuit 1502, the process proceeds to step S106.

  In step S106, it is determined whether or not the video switching time is reached according to the switching time information. If it is determined that it is the switching time, step S106 is YES, and the process proceeds to step S107. If it is determined that it is not the switching time, step S106 is NO, and the process of step S106 is continued.

  In step S107, a priority change command is sent to the memory controller 103 and the bus arbitration circuit. Specifically, the priority order of information for accessing the RAM 102 is determined by the memory controller 103 in accordance with the priority order change command. Further, the priority order for assigning information transfer on the bus is determined by the bus arbitration circuit in accordance with the priority order change command. At this time, the priority order determined for the music information and the lyrics telop for reproducing the accompaniment sound has priority over the transmission speed of the first video information and the second video information. When the priority change command is sent, step S107 is moved to step S108.

  In step S108, it is determined whether or not all the crossfade processes based on the respective switching times have been completed. When all the cross fade processes are completed, the process of step S108 is YES, and the process of the flowchart is terminated. If all the cross fade processes have not been completed, the process of step S108 is moved to step S102.

[About the operation and time passage of the music playback device 1]
The processing of the CPU 100 will be described with reference to FIG. 3 and FIG. In the upper part of FIG. 4, the horizontal axis represents time, and from the upper part of the upper part, the decoded first decoded information, second decoded information, and display information video are represented. In the middle part of FIG. 4, the horizontal axis represents time, the vertical axis represents the bandwidth, and the variation in bandwidth necessary for decoding the first video information and the second video information is represented. In the lower part of FIG. 4, the horizontal axis represents time, and the priority order determined by the memory controller 103 is expressed as priority order 1 to priority order 4 in descending order. The lower row shares the time axis shown in the middle row. The time point at the left end of the time axis shown in FIG. 4 is set as a reproduction start time point (TP1) at which the accompaniment sound is started to be reproduced by the process of step S101.

  In step S101, a first decode command and a playback command are sent. Receiving the first decoding command, the first decoder 140 starts decoding the first video information and generates first decoding information. The first decode information is mixed with the lyrics telop information by the mixer 1504 to generate display information. The display information is sent to the monitor 131, and the monitor 151 displays the video represented by the display information. The order of information of processing with a high priority determined by the memory controller 103 is the order of music information, lyrics telop information, first video information, and second video information, and the allocation band allocated to each processing is determined in this order. It is done.

  In step S102, it is determined whether or not the decoding start time (TP2) has been reached. If the process in step S102 is YES, the process proceeds to step S103. The time point determined as YES in step S102 is the decoding start time point (TP2) shown in FIG.

  In step S103, a second decode command is sent. Receiving the second decoding command, the second decoder starts decoding the second video information using the usable bandwidth at the decoding start time (TP2). The second decoder sends second decode information, which is information obtained by decoding the second video information, to the memory 102 that is the destination of the second decode information included in the second decode command. Bandwidth is determined in the order of music information, lyrics telop information, first video information, and second video information from information of processing with a high priority determined by the memory controller 103. The period from the decoding start time (TP2) to the crossfade display end time (TP5) in step S103 is the crossfade processing period (S2).

  In step S104, it is determined whether or not the crossfade display start time (TP3) has come. If the process in step S104 is YES, the process proceeds to step S105. The time point determined as YES in step S104 is the crossfade start time point (TP3) shown in FIG. In step S105, the first decode information is faded out and the second decode information is faded in.

  As an example, the first decode information and the second decode information shown in the upper part of FIG. 4 indicate information used when three images are cross-fade displayed in the cross-fade display processing period (S1). The output first decode information and second decode information are combined by the mixer 1503 and the mixer 1504 to generate display information. At the time T0 that is the same time as the crossfade display start time (TP3), which is the start time of the crossfade display processing period (S1), the output level of the first decode information is 100%, and the output of the second decode information is output. The level is displayed at 0%. At the time point T1, the output level of the first decode information is 75%, and the output level of the second decode information is 25%. At time T2, which is the same time as the switching time (TP4), the output level of the first decode information is 50%, and the output level of the second decode information is 50%. At time T3, the output level of the first decode information is 75%, and the output level of the second decode information is output at 25%. After the time T4 when the crossfade display processing period (S1) ends, the output level of the first decode information is 0% and the output level of the second decode information is 100%.

  In step S107, the information of the processing with the higher priority determined by the memory controller 103 and the bus arbitration circuit of the bus 170 is determined in order of music information, lyrics telop information, first video information, and second video information. Thereby, the memory controller 103 and the bus arbitration circuit determine the priority of the band after the switching time (TP4).

  After the crossfade display processing period (S1), when all the crossfade processes at the respective switching time points (TP4) have not been completed, the time point (TP1) at the left end of the time axis in FIG. As (TP5), processing for the next cross-fade display processing is started. In the present embodiment, when even-numbered processing is performed, the relationship between the first decode information and the second decode information shown in the upper part of FIG. 4 is reversed. Further, in the priority order of the processing shown in the lower part of FIG. 4, the relationship between the first decoder and the second decoder is reversed. Similarly, the process of the flowchart shown in FIG. 3 is started in a state where the first decoder and the second decoder are reversed.

[Effect of this embodiment]
In the conventional music playback device, the various processes executed by the CPU 100 are for the user to view the accompaniment sound, the lyrics telop, the video, and the user's singing score using a speaker and a monitor. , Processing for transmitting / receiving information to / from the server device, and processing for operating hardware such as an operating system. Information transmitted in these processes is transmitted to each component by the bus 170. When a plurality of processes are executed at the same time, there is a possibility that the amount of information transmitted per unit time may be in an extreme state where the transmission path capacity of the bus 170 exceeds. In particular, when executing the cross-fade process, the first video information to be faded out and the second video information to be faded in are required. For decoding processing, large information is transmitted through the bus 170 as compared with other processing. As shown in FIG. 5, in the conventional crossfade process, two pieces of video information are decoded in the same period. If two pieces of video information are decoded at the same time, there is a high possibility that an extreme state will occur. Therefore, in the present embodiment, as shown in FIG. 4, the decoding start time (TP2) of the second video information is determined from the transmission path capacity of the bus 170 and the use band. Furthermore, since the decoding of the second video information is performed using the surplus bandwidth, the cross-fade process can be reliably performed without being in an extreme state.

  Further, in the music playback device of the present embodiment, the background video displayed when the user sings is configured by combining a plurality of videos, and the cross-fade processing is performed so that the two videos partially overlap. No processing is performed to reproduce a video created in advance so that the video appears to partially overlap. Therefore, it is possible to display a desired video in a crossfade without performing a previous video creation operation.

[Modification 1]
If it is determined in step S106 that the switching time (time TP4 shown in FIG. 4) has been reached, the CPU 100 executes the process of step S107 and changes the priority order determined by the memory controller 103. However, in Modification 1, the surplus bandwidth that changes from moment to moment and the time associated with the second decoding information that has been decoded by the second decoder may be measured. When it is determined from the measurement result that the decoding of the second video information is not in time by the switching time point (time point TP4 shown in FIG. 4), the time point before the switching time point (time point TP4 shown in FIG. 4), or the crossfade display start time point Priorities are changed before (time TP3 shown in FIG. 4), and the decoding of the second decoder is preferentially executed. As an example, new decoding period information can be obtained by dividing the amount of information of the second video information to be displayed in a fade-in manner by the band used for transmission of the second video information among the used bands at the time of determining whether it is in time. Is calculated. In step S100, the period represented by the decoding period information obtained by Expression 2 is compared with the period represented by the new decoding period information when determining whether or not it is in time. When the new decoding period information represents a period longer than the decoding period information obtained in step S100, the CPU 100 changes the priority order of the first video information and the second video information, and changes the second video information to the first video information. Transmission and processing are given priority over video information.

  If the second video information is prioritized, the first video information is not decoded in time by the first decoder, and the time associated with the first video information is not in time, the video indicated by the first video information is not in time. The video immediately before the video is displayed. Thereby, the cross-fade display process is more reliably executed.

[Modification 2]
Although the decoding start time information is obtained by Expression 1 and Expression 2, it may be obtained by Expression 3 and Expression 2 based on crossfade display start time information described later. Furthermore, the cross-fade display start time information of Expression 3 may be appropriately changed by information representing a time point from the cross-fade display start time (TP3) to the cross-fade display end time (TP5) shown in FIG.

[Modification 3]
Priority 1 to priority 4 shown in FIG. 4 are music information for music playback processing, telop information for displaying lyrics telop, first video information decoded by the first decoder, and decoded by the second decoder. Although the case of the priority order for the transmission of the second video information has been described, other processing may be inserted between the priority orders. As an example, when a newly distributed music database is downloaded from a server device on the Internet 200, a priority order and an allocated band for transmitting the downloaded music database are determined. When the priority order for the transmission of the downloaded data becomes the priority order 4, the priority order of the second video information is determined as the priority order 5.

[Modification 4]
The first decoder and the second decoder may be a hardware decoder or a software decoder. Further, the first decoder and the second decoder may be a combination of a hardware decoder and a software decoder.

[Modification 5]
In the crossfading process, the decoded second decode information is temporarily stored in the RAM 102. However, the second decode information may be stored in a memory different from the RAM 102. In that case, a memory is provided between the second decoder 141 or the second decoder 141 and the video controller 150, and the memory stores the second decoding information. The stored second decoding information is read from the memory and sent to the video control unit 150 in accordance with an instruction from the CPU 100. In accordance with an instruction from the CPU 100, it may be read from the memory as read from the RAM 102 in step S105 of the present embodiment. In the case of the fifth modification, since the second decode information read from the memory is not transmitted on the bus 170, the information transmitted on the bus 170 is reduced, and the cross-fade process can be more reliably performed.

[Modification 6]
In the crossfade process, the process of step S100 is performed before the music is played back, but the music may be being played back. In that case, if NO is determined in the process of step S108, the process proceeds to step S100. And step S101 is controlled not to be executed after the second time.

[Correspondence between Claims and Embodiments]
The CPU 100 is an example of a control unit. The RAM 102 is an example of a memory. The CPU 100, the bus 170, and the memory controller 103 are an example of a determination unit. The bus monitor 171 is an example of a bus measurement unit. A combination of the CPU 100, the ROM 101, the RAM 102, the memory controller 103, the HDD 110, and the bus 170 is an example of a computer. The process of step S100 is an example of a generation step. Step S103 is an example of a decoding instruction step. The processing performed by the control unit 100, the second decoder 141, and the video control unit 150 performed from the decoding start time to the crossfade display end time is an example of the crossfade processing.

1 Music player 100 CPU
101 ROM
102 RAM
103 Memory controller 110 HDD
120 Operation Processing Unit 130 Sound Control Unit 140 First Decoder 141 Second Decoder 150 Video Control Unit 160 Communication Unit 170 Bus

Claims (7)

A control unit for controlling various processes for music reproduction;
A first decoder and a second decoder for decoding first video information and second video information representing video to be displayed on the display unit during music reproduction, respectively;
A memory having a temporary storage area for various processes controlled by the control unit;
A bus for transmitting information for processing by the control unit, the first decoder, and the second decoder;
With
The various processes controlled by the control unit include the decoding of the first decoder and the second decoder, the video indicated by the first video information being faded out, and the video indicated by the second video information being faded in. Crossfade display processing, and
The controller is
When controlling the crossfade display processing, it is used for the various processing other than the decoding of both the decoders, the total bandwidth indicating the transmission path capacity of the bus, the bandwidth required for the decoding of the first video information A decoding start time of the second video information is determined based on a band to be processed, and the second decoder starts decoding at the decoding start time prior to controlling the cross-fade display processing. Music player to play. A control unit for controlling various processes for music reproduction;
A first decoder and a second decoder for decoding first video information and second video information representing video to be displayed on the display unit during music reproduction, respectively;
A memory having a temporary storage area for various processes controlled by the control unit;
Buses connected to the control unit and the memory, respectively, for transmitting information;
With
The various processes controlled by the control unit include the decoding of the first decoder and the second decoder, the video indicated by the first video information being faded out, and the video indicated by the second video information being faded in. Crossfade display processing, and
The controller is
When controlling the crossfade display processing, it is used for the various processing other than the decoding of both the decoders, the total bandwidth indicating the transmission path capacity of the bus, the bandwidth required for the decoding of the first video information A decoding start time of the second video information is determined based on a band to be processed, and the second decoder starts decoding at the decoding start time prior to controlling the cross-fade display processing. Music player to play. A bus bandwidth measuring means for measuring a bandwidth used by the bus when the control unit controls the various processes;
The control unit determines a surplus band by subtracting the used band measured by the bus band measuring unit and a band necessary for decoding the first video information from the total band, and the determined surplus band The music playback device according to claim 1 or 2, wherein the decoding start time is determined according to the following. Wherein the control unit, the information amount of the second image information to be used before Symbol crossfade display process, calculates the decode period divided by the surplus bandwidth,
The decoding start time, according to claim 3 you, wherein a point of time before the length of the decode period than a predetermined first time point between the start and end of the cross-fade display processing Music playback device. The various processes include a music playback process and a telop display process,
Determining a priority for transmitting information for the various types of processing, and determining a bandwidth to be allocated for transmitting the information for the various types of processing according to the priority,
The determination unit is
Prioritizing the higher priority processing to determine the allocated bandwidth;
Among the various processes, the priority for transmitting information for music reproduction processing and telop display processing is higher than the priority for transmitting information for decoding of the first decoder and decoding of the second decoder. The priority of transmitting information for decoding by the second decoder at a predetermined second time point from the start to the end of the cross-fade display process is determined so that priority is given to the first decoder. 5. The music reproducing apparatus according to claim 1, wherein priority is given to a priority order of transmitting information for decoding of the music playback apparatus according to claim 1. The cross-fade is determined by the determination unit such that priority for transmitting information for decoding by the second decoder is given priority over priority for transmitting information for decoding by the first decoder; When the decoding of the first video information indicating the video displayed at a predetermined third time point from the start to the end of the display process is not completed by the third time point,
The control unit displays the cross-fade display so that a video is displayed according to the video information decoded at the time closest to the third time among the first video information decoded up to the third time. 6. The music reproducing apparatus according to claim 5, wherein the process is controlled. A control unit for controlling various processes for music reproduction;
A first decoder and a second decoder for decoding first video information and second video information representing video to be displayed on the display unit during music reproduction, respectively;
A memory having a temporary storage area for various processes controlled by the control unit;
Buses connected to the control unit and the memory, respectively, for transmitting information;
On the computer of the music playback device comprising
A decoding control step for controlling decoding of the first decoder and the second decoder;
A cross-fade display step of fading out the video indicated by the first video information and fading in the video indicated by the second video information;
When executing the cross-fade display step, the total bandwidth indicating the transmission path capacity of the bus , the bandwidth required for decoding the first video information, and used for the various processes other than the decoding of the two decoders. A determination step of determining a decoding start time of the second video information based on
A program for a music reproducing apparatus, which causes the second decoder to start decoding at the decoding start time before executing the crossfade display step.