Systems and methods for implementing cross-fading, interstitials and other effects downstream
Systems and methods are presented for cross-fading (or other multiple clip processing) of information streams on a user or client device, such as a telephone, tablet, computer or MP3 player, or any consumer device with audio playback. Multiple clip processing can be accomplished at a client end according to directions sent from a service provider that specify a combination of (i) the clips involved; (ii) the device on which the cross-fade or other processing is to occur and its parameters; and (iii) the service provider system. For example, a consumer device with only one decoder, can utilize that decoder (typically hardware) to decompress one or more elements that are involved in a cross-fade at faster than real time, thus pre-fetching the next element(s) to be played in the cross-fade at the end of the currently being played element. The next elements(s) can, for example, be stored in an input buffer, then decoded and stored in a decoded sample buffer, all prior to the required presentation time of the multiple element effect. At the requisite time, a client device component can access the respective samples of the decoded audio clips as it performs the cross-fade, mix or other effect. Such exemplary embodiments use a single decoder and thus do not require synchronized simultaneous decodes.
1. A method for adjusting audio playback comprising:
downloading a first audio clip, a second audio clip to be played following the first audio clip, and a clip transition to be played at a boundary between the first and second audio clips at a playout controller;
storing the first and second audio clips, and the clip transition at an input buffer;
decoding the first and second audio clips, and the clip transition at a decoder; and
adjusting a download timing and one or more characteristics of the clip transition based at least in part on a performance profile of the playout controller and/or the input buffer using a device performance software agent.
2. The method of claim 1 , wherein the download timing and one or more characteristics of the clip transition are adjusted further in part on a device profile.
3. The method of claim 1 , wherein the download timing and one or more characteristics of the clip transition are adjusted further in part on metadata associated with the first and/or second audio clips.
4. The method of claim 1 , wherein the decoder is configured to decode the audio clips at a faster than real time rate.
5. The method of claim 1 , further comprising:
generating a new signal level, at a cross-fade component, from uncompressed signal levels of two source frames from the first and second audio clips, for a resulting frame of the clip transition based at least in part on a cross-fade mix, blend or other transition effect blend rate.
6. The method of claim 1 , wherein the one or more characteristics adjustable by the device performance software agent include a real-time management of the downloading and/or decoding of the audio clips based on system resource availability.
7. A method for adjusting audio playback comprising:
downloading a first audio clip, a second audio clip to be played following the first audio clip, and a clip transition to be played at a boundary between the first and second audio clips at a playout controller;
storing the first and second audio clips, and the clip transition at an input buffer;
decoding the first and second audio clips, and the clip transition at a first decoder and a second decoder; and
adjusting a download timing and one or more characteristics of the clip transition based at least in part on a performance profile of the playout controller and/or the input buffer using a device performance software agent.
8. The method of claim 7 , wherein the download timing and one or more characteristics of the clip transition are adjusted further in part on a device profile.
9. The method of claim 7 , wherein the download timing and one or more characteristics of the clip transition are adjusted further in part on metadata associated with the first and/or second audio clips.
10. The method of claim 7 , wherein the decoder is configured to decode the audio clips at a faster than real time rate.
11. The method of claim 7 , further comprising:
generating a new signal level, at a cross-fade component, from uncompressed signal levels of two source frames from the first and second audio clips, for a resulting frame of the clip transition based at least in part on a cross-fade mix, blend or other transition effect blend rate.
12. The method of claim 7 , wherein the one or more characteristics adjustable by the device performance software agent include a real-time management of the downloading and/or decoding of the audio clips based on system resource availability.