[whatwg] Video : Slow motion, fast forward effects
singer at apple.com
Thu Aug 7 12:16:21 PDT 2008
At 12:11 -0700 7/08/08, Jonas Sicking wrote:
>Dave Singer wrote:
>>At 20:10 +1200 7/08/08, Chris Double wrote:
>>>On Thu, Aug 7, 2008 at 6:20 PM, Ian Hickson <ian at hixie.ch> wrote:
>>>> On Thu, 7 Aug 2008, Biju Gm at il wrote:
>>>>> On Thu, Aug 7, 2008 at 1:49 AM, Ian Hickson <ian at hixie.ch> wrote:
>>>>> > playbackRate is the right way to do it, but maybe Firefox doesn't yet
>>>>> > support it.
>>>>> So can I assume HTML5 spec also allow playbackRate to be negative value.
>>>>> ie to support go backward at various speed....
>>>Would you expect the audio to be played backwards too?
>>I think that's extra credit and optional. As you say, even with
>>audio coded in independent frames you have to flip the samples,
>>which is a pain. For audio with forward dependencies, correct
>>decoding means decoding forwards and then flipping whole chunks of
>>timeline (though AAC doesn't suffer too badly if you don't do this,
>>by the way).
>Honestly, this seems useless enough that the spec should just say
>that when playback is less than 0 sound should be turned off. I'd
>hate to see engineers working on this just because "the spec says it
>should work that way".
I'm sorry if I wasn't clear: I agree. If you want your
implementation to shine, or be used heavily for audio scrubbing, or
something, go ahead and implement. But it should not be required.
("For extra credit")
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