Playback of media data at reduced speed

Abstract

A method for reproducing, i.e., playing back, media data includes: receiving media data in a receive buffer; determining whether the receive buffer is sufficiently filled; reducing the playback speed over a period until the receive buffer is sufficiently filled, and playing back the media data at the reduced playback speed. The reduced playback speed has a speed profile having at least one non-linear section.

Claims

1. A method of synchronizing switching over playback from a first media data source to a second media data source, said method comprising: receiving media data from the first media data source; recognizing that the same content that is received from the first media data source is also receivable from the second media data source, delayed by a first time period; buffering the media data received from the first media data source in a reception buffer; receiving media data from the second media data source in the reception buffer; establishing whether the reception buffer is sufficiently filled; while the reception buffer is not sufficiently filled, reproducing the media data received from the first media data source, wherein the reproduction speed of the media data received from the first media data source and buffered in the first reception buffer is reduced over a period of time until the reception buffer is sufficiently filled; overlaying the media data received from the first media data source with a media effect when the reproduction speed has been reduced; and seamlessly switching over playback, once the reception buffer is sufficiently filled, so as to reproduce the media data from the second media data source.

2. The method as claimed in claim 1, further comprising: matching a pitch of the reproduced media data received from the first media data source to the reduced reproduction speed.

3. The method as claimed in claim 1, wherein the media data comprise audio and/or video data.

4. The method as claimed in claim 1, wherein the media data are transmitted via a wireless link.

5. The method of claim 1, wherein: the reduced reproduction speed has a speed profile having at least one nonlinear section, the speed profile has a first section in which the reproduction speed has a positive curvature, and the speed profile has a second section in which the reproduction speed has a negative curvature.

6. The method of claim 1, wherein the first media data source is an analog media source and the second media data source is a digital media source.

7. A media reproduction apparatus for reproducing media data, comprising: a reception device that receives the media data from the first media data source and the media data from the second media data source; a reception buffer that buffer-stores the received media data from the first media data source and the received media data from the second media data source; and a reproduction device that reproduces the stored media data from the reception buffer, wherein the media reproduction apparatus carries out the method as claimed in claim 1.

8. The media reproduction apparatus as claimed in claim 7, wherein the media reproduction apparatus is a radio tuner, a head unit or a set of headphones.

9. The media reproduction apparatus as claimed in claim 7, wherein the media effect is stored in the media reproduction apparatus.

10. A vehicle having a media reproduction apparatus as claimed in claim 7.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Exemplary embodiments of the invention are described in detail below with reference to the accompanying figures, in which:

(2) FIG. 1 shows a vehicle having a media reproduction apparatus according to an embodiment of the invention;

(3) FIG. 2 shows a flowchart for a method for reproducing media data according to an embodiment of the invention; and

(4) FIG. 3 shows a speed profile for the reproduction of media data according to an embodiment of the invention.

(5) In principle, identical or similar parts are provided with the same reference symbols.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

(6) FIG. 1 shows a vehicle 10 having media reproduction apparatuses 12a, 12b, in the form of an automobile radio or a head unit 12a and a set of headphones 12b.

(7) The automobile radio 12a or the head unit 12a can receive digital and analog radio programs via a radio link 14a using a reception device (tuner) 16a and can reproduce the radio programs via a reproduction device 18a in the interior of the vehicle 10, for example via loudspeakers.

(8) The media data from a digital radio program are stored in a reception buffer 20a prior to reproduction before being processed further by the reproduction device 18a and converted into an analog signal.

(9) As an alternative to reproduction in the interior of the vehicle 10, the media data can be transmitted in digital form via an infrared link 14b or a radio link 14b to the reception device 16b of the set of headphones 12b. There, the media data are buffer-stored in a reception buffer 20b and output to an ear loudspeaker by a reproduction device 18b.

(10) FIG. 2 shows a flowchart for a method for reproducing media data that can be carried out by the automobile radio 12a, or the head unit 12a, or the set of headphones 12b.

(11) In a step 30, media data are received in a reception buffer 20a, 20b. By way of example, the media data are received by the automobile radio 12a or the head unit 12a and particularly the tuner 16a via the radio link 14a and buffer-stored in the reception buffer 20a. Similarly, the reception device 16b of the set of headphones 12b can receive media data via the link 14b and buffer-store the media data in the reception buffer 20b.

(12) In a step 32, it is established whether the reception buffer 20a, 20b is sufficiently filled. By way of example, the reception buffer may be sufficiently filled if it is at least 80% filled or it contains media data for at least the next two seconds.

(13) If the reception buffer 20a, 20b is sufficiently filled, the media data are reproduced at normal reproduction speed by the reproduction apparatus 18a, 18b in a step 34.

(14) If the reception buffer 20a, 20b is not sufficiently filled, the reproduction speed is reduced over a period of time in a step 36. In this case, the period of time may be chosen such that the reception buffer is sufficiently filled again at the end of the period of time. By way of example, the period of time has a predefined length.

(15) By way of example, a driver of the vehicle 10 can switch on the automobile radio 12a and select an analog FM station. The automobile radio 12a recognizes that the same radio station can also be received in digital quality using DAB, but with a time delay of three seconds. The automobile radio 12a. or the head unit 12a then reduces the reproduction speed smoothly to 95%. As a result, in one minute the reception buffer 20a can be filled with three seconds. A seamless change between DAB and FM is then possible.

(16) FIG. 3 shows a graph with a possible speed profile 50 for the reproduction of media data. In step 36, to reduce the reproduction speed, the speed profile 50 with at least one nonlinear section 52, 54 is produced or selected.

(17) By way of example, the speed profile 50 is stored in the corresponding reproduction apparatus 12a, 12b or calculated therein.

(18) In the graph, time t is plotted to the right and reproduction speed v is plotted upward. In this case, a reproduction speed of 100% corresponds to a normal reproduction speed.

(19) In the graph, it can be seen that the speed profile 50 has reduced speeds during a period of time 56. In this period of time 56, the reproduction speed rises nonlinearly from 0% to 100%. In a first section 52, the reproduction speed has a positive curvature and the gradient of the curve increases. In a second section 54, the reproduction speed has a negative curvature and the gradient of the curve decreases. In this way, it is possible to achieve a continuous transition for the reproduction speeds in the period of time 56.

(20) The speed profile 50 can additionally be modeled such that the effect of a starting analog reproduction appliance, such as a tape drive or a record player, arises.

(21) In a step 38, the media data are reproduced at reduced reproduction speed by the reproduction apparatus 18a, 18b. In addition, a media effect, such as crackling, can be overlaid with the reproduced media data in this step. The media effect may be stored in the corresponding media reproduction apparatus 12a, 12b.

(22) The reception device 16a or the radio tuner 16a can be located in a separate tuner box, for example, that supplies the head unit 12a with a desired radio program by a digital audio stream.

(23) The head unit 12a or the set of headphones 12b contains a reception buffer 20b of three seconds, for example.

(24) The radio listener in the vehicle 10 can then change the tuned station. The tuner box or the reception device 16a starts sending the new audio stream or the audio data to the head unit 12a or the reproduction apparatus 18a thereof. The latter uses the first data packets that arrive to output an audio signal. Since the audio data may still have interference or be incomplete (the stabilizing reception buffer 20b not yet being filled at this time), the audio signal is mixed with the sound of a pickup coming down onto a record in order to conceal any interference. In addition, the speed profile 50 is used to simulate the reproduction speed of a record starting to turn. This slowing allows the reception buffer 20b to be filled with at least one second fairly quickly, which is sufficient for fairly interference-free operation. Within the next minute, the reception buffer 20b is filled to a target level by virtue of the reproduction speed of the audio signal initially remaining indistinguishably reduced.

(25) In addition, it should be pointed out that “comprising” does not exclude other elements or steps, and “a” or “an” does not exclude a large number. Furthermore, it should be pointed out that features or steps that have been described with reference to one of the above exemplary embodiments can also be used in combination with other features or steps from other exemplary embodiments described above.

(26) Reference symbols in the claims should not be regarded as a restriction.

(27) Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.