Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
  • H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
  • H04N21/24—Monitoring of processes or resources, e.g. monitoring of server load, available bandwidth, upstream requests
  • H04N21/2401—Monitoring of the client buffer
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04H—BROADCAST COMMUNICATION
  • H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
  • H04H20/26—Arrangements for switching distribution systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04H—BROADCAST COMMUNICATION
  • H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
  • H04H20/20—Arrangements for broadcast or distribution of identical information via plural systems
  • H04H20/22—Arrangements for broadcast of identical information via plural broadcast systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
  • H04L65/80—Responding to QoS
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
  • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
  • H04N21/439—Processing of audio elementary streams
  • H04N21/4392—Processing of audio elementary streams involving audio buffer management
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
  • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
  • H04N21/44—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs
  • H04N21/44004—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs involving video buffer management, e.g. video decoder buffer or video display buffer
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N5/00—Details of television systems
  • H04N5/76—Television signal recording
  • H04N5/78—Television signal recording using magnetic recording
  • H04N5/782—Television signal recording using magnetic recording on tape
  • H04N5/783—Adaptations for reproducing at a rate different from the recording rate

Definitions

• the invention relates to a method for reproducing media data, a media player and a vehicle. Background of the invention
• Digital media data are stored after reception in a receive buffer to compensate for the mostly non-continuous transmission of digital data in packets. For example, when digital audio data and / or video data is transferred from a source to the sink, buffering of the data on the receiver side is almost always necessary for stable and interference-free reproduction in order to compensate for fluctuations in data transmission (jitter). Since the buffer first has to be filled before the start of the playback, playback usually starts delayed. This becomes noticeable, for example, when switching from one audio stream to another. A similar problem can occur when you want to synchronize different media sources.
• An example of this is a car radio that can receive the same radio station both analogue via FM and digitally via DAB.
• the radio can occasionally switch between the playback of the analog or the digital signal.
• the audio signal can be temporal between the two reception channels mentioned be delayed. If one wishes to carry out the changes as suitably as possible, an adjustment in the receiver must therefore take place by delaying the leading signal via a buffering.
• the selected audio source can not be played back immediately, but first the receiving buffer is filled.
• the media data may include, for example, audio and / or video data.
• the method comprises the steps of:
• the digital media data is received in data packets that are initially stored in a receive buffer. Is the receive buffer empty or insufficient? filled, to ensure continuous playback of the media data at a normal playback speed, the playback speed will be temporarily re prised ⁇ , so that the media data is reproduced slowly arrive as new media data. This may fill the receive buffer.
• a situation in which the receiving buffer is not sufficiently filled for example, occur when a program or a media stream is changed, as is the case when changing a radio program, for example. Also may occur such a situation, when a reproduction of the media data is started, for example, at the start of a media ⁇ reproduction, such as when a headset is turned on. In all these situations, media playback may start immediately when the first media data of the selected media source arrives at the receiver.
• the reduced playback speed to a speed profile having we ⁇ ilias a non-linear portion need not be constant, but may increase or decrease. In this way, transitions between playback speeds that differ greatly can be balanced out more harmoniously.
• the time required to fill a reception buffer can be concealed without having to reproduce a signal from a wrong media source or mute the media playback.
• the speed profile has a portion in which the re ⁇ reproduction speed more than linear increases.
• the playback speed increases with time, the time change of the playback speed with increas ⁇ mender time increases.
• the playback speed increases with time, with the time change of the playback speed decreasing with increasing time.
• a transition between a reproducing speed almost equal to the normal reproducing speed and the normal reproducing speed can be modeled.
• the method further comprises the step of:
• an audio signal can be superimposed with other sounds, such as the crackle of a Turntable, or the sound of a rotating tape drive ⁇ plant.
• the time can be bridged with the actual (but slowed down) audio signals, and possibly made as acceptable as possible by adding audio effects to the listener.
• Another possibility is not to put the audio signal immediately on the speakers, but to delay, for example, a second. This allows the buffer to be filled for one second. In order not to hear silence from the speakers for a second, the typical noise of a radio tuned through the FM band could be recorded. A modern tuner is usually so fast that there is virtually no delay due to tuning. The Tune noise can therefore be an audio sample, which is simply recorded at the right time. For receivers with analog double tuner, while a tuner is already at the target frequency and fills the buffer, the second tuner can tune through the band and produce the typical effect.
• the method further comprises the step of:
• the audio data can be reproduced in such a way that the pitch is increased by the same factor as the playback speed is reduced.
• Corresponding signal processing can be used to correct the pitch, which can be falsified by the speed change. So slight changes should only be noticed by a few listeners.
• the media data is transmitted over a cordless connection.
• the cordless connection may include a radio link and / or an infrared link.
• radio programs can be transmitted via a digital radio link. It is too possible that a data transmission from a radio receiver to a headphone takes place via an infrared connection.
• the media player may include, for example, a radio tuner, a car radio, a head unit, i. a main unit, which may be located in the center console of a vehicle, or a headphone.
• the media playback device comprises a receiving device for receiving digital media data, for example a radio receiver or an infrared receiver; a receive buffer for buffering received media data; and a reproducing device for reproducing media data from the reception buffer.
• the playback device may include, for example, a speaker or a display.
• the media player can perform the method of any one of the preceding claims, i. H. For example, reduce the playback speed of the media data when the receiving buffer must be replenished. It should be understood that features of the method as described above and below may also be features of the media player and vice versa.
• the vehicle may be, for example, a car, truck, motorcycle or bus.
• FIG. 1 shows a vehicle with a media playback device according to an embodiment of the invention.
• FIG. 2 shows a flowchart for a method for reproducing media data according to an embodiment of the invention.
• Fig. 3 shows a velocity profile for rendering media data according to an embodiment of the invention. Basically, identical or similar parts are provided with the same reference numerals.
• FIG. 1 shows a vehicle 10 having two media players 12a, 12b, in the form of a car radio 12a and a headphone 12b.
• the car radio 12a or the head unit 12a can receive digital and analog radio programs via a radio link 14a with a receiving device (tuner) 16a and reproduce them via a display device 18a in the interior of the vehicle 10, for example via loudspeakers.
• the media data of a digital radio program is stored in a reception buffer 20a prior to reproduction before being further processed by the reproduction device 18a and converted into an analog signal.
• the media data can be transmitted in digital form via an infrared connection 14b or a radio connection 14b to the receiving device 16b of the headphone 12b. There, the media data are buffered in a receive buffer 20b and output from a display device 18b to an ear speaker.
• FIG. 2 shows a flow chart for a method for reproducing media data that can be performed by the car radio 12a or the head unit 12a or the headphone 12b.
• media data is received in a receive buffer 20a, 20b.
• the media data are received by the car radio 12a or the head unit 12a and in particular the tuner 16a via the radio link 14a and buffered in the reception buffer 20a.
• the receiving device 16b of the headphone 12b can receive media data via the connection 14b and buffer it in the receiving buffer 20b.
• a step 32 it is determined whether the reception buffer 20a, 20b is sufficiently filled. For example, if it is at least 80% full or contains media data for at least the next two seconds, the receive buffer may be filled enough.
• the media data are reproduced in a step 34 with the reproduction device 18a, 18b at normal playback speed.
• the playback speed is reduced over a period of time in a step 36.
• the period of time can be chosen so that the receiving buffer is sufficiently filled again at the end of the time segment.
• the period of time has a predefined length.
• a driver of the vehicle 10 may turn on the car radio 12a and select an analog FM transmitter.
• the car radio 12a recognizes that the same radio station can also be received by DAB in digital quality, but with a time delay of three seconds. Now the car radio 12a and the head unit 12a gently reduce the playback speed to 95%. As a result, the receive buffer 20a can be filled by 3 seconds in one minute. Now a seamless change between DAB and FM is possible.
• FIG. 3 shows a diagram with a possible velocity profile 50 for the reproduction of media data.
• the speed profile 50 with at least one non-linear section 52, 54 is created or selected.
• the velocity profile 50 is in the ent ⁇ speaking playback device 12a, 12b or stored is calculated there.
• the velocity profile 50 has reduced velocities during a period 56.
• the reproduction speed increases from 0% to 100% in a non-linear manner.
• the playback speed is positively curved, the slope of the curve increases.
• the playback speed is negatively curved, the slope of the curve decreases. In this way, a continuous transition of the playback speeds in the time section 56 can be achieved.
• the speed profile 50 can also be modeled so that the effect of a anfahrenden analog Wiederga- beelecommunications, such as a tape drive or a disk player's ⁇ arises.
• a step 38 the media data is reproduced with the playback device 18a, 18b at a reduced playback speed. Additionally, in this step, a
• Media effect such as crackle, be superimposed with the reproduced media data.
• the media effect may be in the corresponding media playback device 12a, 12b stored.
• the receiving device 16a or the radio tuner 16a can be located, for example, in a separate tuner box, which supplies the head unit 12a with a desired radio program via a digital audio stream.
• a reception buffer 20b of three seconds is provided.
• the radio listener in the vehicle 10 can now change the tuned station.
• the tuner box or the receiving device 16a starts the transmission of the new audio stream or the audio data to the head unit 12a or its reproduction device 18a.
• This uses the first incoming data packets to output an audio signal. Since the audio data may still be disturbed or incomplete (the stabilizing receive buffer 20b is not yet filled at this time), the audio signal is mixed with the sound of a pickup placed on a record to conceal any interference.
• the speed profile 50 simulates the playback speed of a spinning record. Due to this slowing down, the receiving buffer 20b can be filled up very quickly at least by one second, which is sufficient for a fairly trouble-free operation. Within the next minute, the reception buffer 20b is filled to its nominal level by initially slightly reducing the playback speed of the audio signal.

Landscapes

• Engineering & Computer Science (AREA)
• Signal Processing (AREA)
• Multimedia (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing For Digital Recording And Reproducing (AREA)
• Circuits Of Receivers In General (AREA)
• Fittings On The Vehicle Exterior For Carrying Loads, And Devices For Holding Or Mounting Articles (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=48948412

Family Applications (1)

Country Status (5)

Families Citing this family (4)

Citations (3)

Family Cites Families (17)

• 2012
  • 2012-08-29 DE DE102012215352.7A patent/DE102012215352A1/de not_active Ceased
• 2013
  • 2013-08-06 WO PCT/EP2013/066438 patent/WO2014032913A1/de active Application Filing
  • 2013-08-06 EP EP13745837.8A patent/EP2891258A1/de not_active Ceased
  • 2013-08-06 US US14/424,554 patent/US9781454B2/en active Active
  • 2013-08-06 CN CN201380045156.5A patent/CN104584466B/zh active Active

Patent Citations (3)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events