WO2015129033A1

WO2015129033A1 - Disk playback device

Info

Publication number: WO2015129033A1
Application number: PCT/JP2014/055104
Authority: WO
Inventors: 直登西口
Original assignee: 三菱電機株式会社
Priority date: 2014-02-28
Filing date: 2014-02-28
Publication date: 2015-09-03
Also published as: JPWO2015129033A1; JP5933869B2

Abstract

The present invention acquires the frame rate of a clip information file recorded at the beginning of a file system of an optical disk (d) and sets said frame rate as the initial frame rate of a video output before video stream decoding has started. The video is output at this initial frame rate before and after the start of the video stream decoding.

Description

Disc player

The present invention relates to a disc playback apparatus for playing back AV content recorded on a disc such as Blu-ray Disc (registered trademark; hereinafter referred to as “BD”).

Patent Document 1 discloses a conventional technique aimed at reproducing AV content without interruption. In Patent Document 1, a signal format of a play item having the longest reproduction time is detected from AV contents composed of a plurality of play items, and the signal format of the other play item is detected as the signal format of the detected play item. Has been converted.
By converting to the signal format of the play item having the longest playback time in this way, even when AV content including a play item of a different signal format is played back, authentication processing does not occur in the middle, and the AV content is It is possible to play without interruption.

JP 2011-44213 A

When playing back a BD-J (Blu-ray Disc Java (registered trademark; hereinafter omitted)) title, AV video decoding does not start immediately, but only the BD-J graphics screen Is output at a frame rate (hereinafter referred to as an initial frame rate) set in advance with respect to the video output before decoding of the first video stream is started.
Thereafter, when the decoding of the first video stream is started, if the frame rate of the video stream is different from the initial frame rate, a frame rate conversion process from the initial frame rate to the frame rate of the video stream is performed. . In this case, since the frame rate is converted in spite of being reproduced, there has been a problem that the output video is temporarily deteriorated (noise generation or mute video output).

Note that the conventional technique described in Patent Document 1 targets a state in which a video stream is decoded and the signal format of the video stream is recognized. That is, as described above, even when playback of AV content is started, decoding of a video stream is not started immediately, and an initial state in which only a BD-Java graphics screen is output is not assumed. For this reason, the technique described in Patent Document 1 cannot cope with the case where the initial frame rate of the video output of the BD-J graphics is different from the frame rate of the video stream that is first decoded.

The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a disc playback apparatus capable of preventing temporary degradation of output video due to frame rate conversion during content playback. And

The disc playback device according to the present invention is a disc playback device for playing back AV content recorded on a disc, acquires the frame rate in the clip information file recorded at the head on the file system of the disc, and acquires the AV content. A control unit that sets the initial frame rate of the video output before starting the decoding of the video stream, and a playback unit that outputs the video before and after starting the decoding of the video stream at the initial frame rate.

According to the present invention, there is an effect that it is possible to prevent temporary deterioration of the output video accompanying the frame rate conversion during the reproduction of the content.

It is a block diagram which shows the structure of the disc reproducing | regenerating apparatus concerning Embodiment 1 of this invention. It is a figure which shows the directory structure in the file system of BD. 4 is a flowchart showing an operation of the disc reproducing apparatus according to the first embodiment. FIG. 3 is a diagram illustrating a relationship between a BD-J graphics frame rate, a video stream frame rate, and an initial background frame rate.

Hereinafter, in order to describe the present invention in more detail, modes for carrying out the present invention will be described with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 is a block diagram showing a configuration of a disk reproducing apparatus according to Embodiment 1 of the present invention. In FIG. 1, a disc playback device 1 is a device for playing back AV content recorded on an optical disc d such as a BD, CD, DVD, etc., and includes a drive 2, a decoder 3, and a microcomputer (hereinafter referred to as a microcomputer) 4. A buffer memory 5a, a main memory 5b, a local storage 5c, a video D / A converter 6 and an audio D / A converter 7.

The drive 2 is a component that reads and demodulates data recorded on the optical disk d, and includes a pickup 2a and a demodulator 2b. The pickup 2a irradiates the optical disk d with laser light, receives the reflected light, and reads data recorded on the optical disk d. The demodulator 2b demodulates the data read from the optical disc d by the pickup 2a, and outputs the demodulated data to the decoder 3 via an ATA (Advanced Technology Attachment) interface (ATA I / F).

The decoder 3 decodes the demodulated data input from the demodulator 2b via the ATA I / F. That is, the decoder 3 temporarily caches the demodulated data input from the demodulator 2b in the buffer memory 5a. Thereafter, the decoder 3 expands the demodulated data cached in the buffer memory 5a to the main memory 5b, and decodes the video stream and the audio stream included in the demodulated data. The local storage 5c stores download data such as an update file of content recorded on the optical disc d.

The microcomputer 4 is a control unit that controls the operation of the internal configuration of the disc playback apparatus 1.
If the microcomputer 4 determines that the type of the optical disc d mounted on the disc playback apparatus 1 is BD and the application format is the BDMV format, the clip information recorded at the head of the file system of the optical disc d is recorded. Get the frame rate included in the file. Then, the microcomputer 4 sets the frame rate of the clip information file as the initial frame rate of the background video output before the decoding of the first video stream is started.

The decoder 3 functions as a playback unit that outputs video before and after the start of decoding of the first video stream at the initial frame rate.
For example, the decoder 3 executes a BD-J program read from the BD and expanded in the main memory 5b, and outputs a video image of BD-J graphics at the initial frame rate. The decoder 3 decodes the first video stream and outputs video at the initial frame rate.

The video D / A converter 6 encodes the video stream decoded by the decoder 3. The video signal converted into an analog signal by the video D / A converter 6 is output from the monitor 6a at the initial frame rate.
The audio D / A converter 7 encodes the audio stream decoded by the decoder 3. The audio signal converted into an analog signal by the audio D / A converter 7 is output as audio from the speaker 7a.

FIG. 2 shows the directory structure in the BD file system. As shown in FIG. 2, in the BD file system, a BDMV directory is placed directly under the root directory (ROOT). The BDMV directory is a directory in which data such as AV content and management information thereof is recorded. Under the BDMV directory, there are a PLAYLIST directory, a CLIPINF directory, and the like. bdmv and Movie Object. Two types of bdmv files are arranged.

In the PLAYLIST directory, there is a playlist information file with an extension “mpls” as shown in FIG. This playlist information file is a file for storing playlist information, in which playback sections (In Time and Out Time) of the AV stream are recorded. The playlist information is information that prescribes playback sections on the time axis of the AV stream and logically designates the playback order of the playback sections. Whether to develop the scene in order is specified.

In the CLIPINF directory, there is a clip information file with an extension clpi. A clip information file has a one-to-one correspondence with each AV stream. In addition to information such as the AV stream encoding format, frame rate, bit rate, and resolution, the beginning of a GOP (Group Of Pictures) EP_map indicating the position is included.

The clip information file recorded at the head of the BD file system is the clip information file “0000.clpi” at the head of the CLIPINF directory shown in FIG. The clip information file “0000.clpi” generally or stochastically matches the frame rate of the AV stream decoded at the beginning of the first play title, and the frame rate of the video stream in this AV stream is set. ing.
The first play title is a title that is automatically played back when the BD is mounted on the disc playback apparatus 1, and is used for a warning to a viewer or a logo display by a content provider.

When the AV content recorded on the BD is reproduced and only the BD-J graphics video is output first, the AV stream of the first play title is decoded subsequently. Accordingly, by setting the frame rate of the clip information file “0000.clpi” as the initial frame rate, the video output of the BD-J graphics and the video output of the video stream subsequent thereto are performed at the same frame rate. . As a result, the frame rate conversion process during the reproduction of AV content is avoided, and it is possible to prevent temporary deterioration of the video accompanying this.

Next, the operation will be described.
FIG. 3 is a flowchart showing the operation of the disc playback apparatus 1 according to the first embodiment. After the optical disc d is inserted into the drive 2 of the disc playback device 1, the AV content recorded on the optical disc d is played back. The flow of the process which sets the initial frame rate of the background video output until it starts is shown.
When the optical disc d is inserted into the drive 2 and mounted on the disc playback apparatus 1, the microcomputer 4 completes the media recognition of the optical disc d based on the management information read from the optical disc d by the drive 2 and decoded by the decoder 3 (step ST1). .

If it is determined by the media recognition that the application format of the optical disc d is not the BDMV format (step ST2; NO), the playback of the AV content recorded on the optical disc d is continued without setting a new initial frame rate. The
On the other hand, when it is determined that the type of the optical disk d is BD and the application format is the BDMV format (step ST2; YES), the microcomputer 4 determines the frame rate in the clip information file recorded at the head on the BD file system. Is acquired (step ST3). Specifically, the drive 2 reads the clip information file “0000.clpi” at the head of the CLIPINF directory, and the decoder 3 decodes the clip information file. The microcomputer 4 acquires the frame rate from this decoded data.

Next, when the frame rate acquired in step ST3 is 24 fps, 30 fps, or 60 fps (step ST4; 24/30/60 fps), the microcomputer 4 sets 60 fps as the initial frame rate for background video output in the decoder 3. (Step ST5).
If the frame rate acquired from the clip information file is 25 fps or 50 fps (step ST4; 25/50 fps), the microcomputer 4 sets 50 fps as the initial frame rate for background video output in the decoder 3 (step ST4). ST6).

FIG. 4 is a diagram showing the relationship between the BD-J graphics frame rate, the video stream frame rate, and the background initial frame rate.
A period T1 shown in FIG. 4A is a period from when the BD is mounted on the disc playback apparatus 1 and AV content playback is started to before decoding of the first video stream is started. During this period T1, BD-J graphics are drawn and output at the initial frame rate of the background video output.
The period T2 is a period in which the video output of the video stream is performed after the period T1 has elapsed and the decoding of the first video stream is started. In period T2, the video stream is decoded at a frame rate preset in the corresponding clip information file, and a video signal is output.

Conventionally, the initial frame rate in the period T1 and the frame rate preset in the video stream in the period T2 may be different. In this case, it is necessary to convert the frame rate of the video output from the initial frame rate to the frame rate of the video stream. For this reason, the output video of the video stream is temporarily deteriorated (noise is generated or the mute video is output) at the time surrounded by the broken line in FIG.

On the other hand, in the present invention, when it is determined that the optical disc d is loaded and the application format is the BDMV format by media recognition, as shown in FIG. 4 (b), it is recorded at the head on the BD file system. The frame rate of the clip information file is set as the initial frame rate of the background video output in the period T1.
Since the clip information file generally corresponds to the video stream decoded first in the first play title, the frame rate in the period T1 + T2 shown in FIG. The frame rate is set. As a result, the frame rate conversion process does not occur when the decoding of the video stream is started.

As described above, according to the first embodiment, the microcomputer 4 acquires the frame rate in the clip information file recorded at the head on the file system of the optical disc d, and starts decoding the video stream of the AV content. Set as the initial frame rate of the video output before being played. Then, the decoder 3 performs video output before and after starting the decoding of the video stream at the initial frame rate.
With this configuration, when the clip information file corresponds to a video stream decoded at the beginning of the first play title, the BD-J graphics drawing and the frame rate of this video stream reproduction match, so that the frame The rate conversion process is not performed. Therefore, it is possible to prevent temporary deterioration of the output video accompanying the frame rate conversion during playback of AV content, and to ensure video continuity. As a result, it is possible to perform video output that does not cause discomfort to the user.

In the first embodiment, the frame rate in the clip information file recorded at the head on the BD file system is acquired and set as the initial frame rate. However, the clip information file recorded at the beginning of the BD file system may not correspond to the video stream decoded at the beginning of the first play title. Therefore, the microcomputer 4 is configured to acquire the frame rate of the video stream decoded at the beginning of the first play title and set it as the initial frame rate in the video output before the decoding of this video stream is started. Also good.
Even if comprised in this way, the temporary degradation of the output image | video accompanying the frame rate conversion during reproduction | regeneration of AV content can be prevented, and the continuity of an image | video can be ensured.

In the case of the above configuration, the microcomputer 4 analyzes not only the clip information file recorded at the top of the BD file system but also other clip information files in the CLIPINF directory, and analyzes these clip information files. Among them, it is necessary to specify the one corresponding to the video stream decoded at the beginning of the first play title. Therefore, a plurality of clip information files in the CLIPINF directory need to be predecoded between the start of playback of the BD AV content and the start of decoding of the first video stream. Improving performance is essential.

In the present invention, any component of the embodiment can be modified or any component of the embodiment can be omitted within the scope of the invention.

The disc reproducing apparatus according to the present invention can be applied to an in-vehicle disc reproducing apparatus.

1 disc player, 2 drive, 2a pickup, 2b demodulator, 3 decoder, 4 microcomputer, 5a buffer memory, 5b main memory, 5c local storage, 6 video D / A converter, 6a monitor, 7 audio D / A converter, 7a Speaker.

Claims

A disc playback device for playing back AV content recorded on a disc,
A control unit that obtains a frame rate in a clip information file recorded at the head on the file system of the disc and sets it as an initial frame rate of video output before the decoding of the video stream of the AV content is started;
A disc playback apparatus comprising: a playback unit that outputs video before and after starting decoding of the video stream at the initial frame rate.
A disc playback device for playing back AV content recorded on a disc,
A control unit that obtains a frame rate of a video stream to be decoded first of a first play title and sets it as an initial frame rate of video output before the decoding of the video stream is started;
A disc playback apparatus comprising: a playback unit that outputs video before and after starting decoding of the video stream at the initial frame rate.