[whatwg] HTML5 video: frame accuracy / SMPTE
silviapfeiffer1 at gmail.com
Sun Jan 9 14:41:39 PST 2011
Is it possible to share that video? I wouldn't mind encoding it into
WebM and Ogg, too, and seeing how those work.
Also, this will be very useful for experiments with timing and WebVTT.
On Sun, Jan 9, 2011 at 8:14 PM, Rob Coenen <coenen.rob at gmail.com> wrote:
> I have written a simple test using a H264 video with burned-in timecode
> (every frame is visually marked with the actual SMPTE timecode)
> Webkit is unable to seek to the correct timecode using 'currentTime', it's
> always a whole bunch of frames off from the requested position. I reckon it
> simply seeks to the nearest keyframe?
> On Fri, Jan 7, 2011 at 5:02 PM, Eric Carlson <eric.carlson at apple.com> wrote:
>> On Jan 7, 2011, at 8:22 AM, Rob Coenen wrote:
>> > are there any plans on adding frame accuracy and/or SMPTE support to
>> > video?
>> > As far as I know it's currently impossible to play HTML5 video
>> > frame-by-frame, or seek to a SMPTE compliant (frame accurate) time-code.
>> > The nearest seek seems to be precise to roughly 1-second (or nearest
>> > keyframe perhaps, can't tell).
>> > Flash seems to be the only solution that I'm aware of that can access
>> > on a frame-by-frame basis (even though you the Flash Media Server to make
>> > work).
>> > Seeking to a SMPTE time-code is completely impossible with any solution I
>> > have looked at.
>> > Very interested to learn what the community POV is, and why it isn't
>> > implemented.
>> 'currentTime' is a double so you should be able to seek more accurately
>> than one second - modulo the timescale of the video file and how the UA
>> supports seeking to inter-frame times.
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