[whatwg] HTML5 video: frame accuracy / SMPTE

[Kevin Marks]

If you really want to test timecode, you need to get into SMPTE drop-frame
timecode too (possibly the single most annoying standards decision of. all
time was choosing 30000/1001 as the framerate of NTSC video)

Eric, can you make BipBop movie for this? - Like the ones used in this demo:

http://developer.apple.com/library/mac/#documentation/NetworkingInternet/Conceptual/StreamingMediaGuide/UsingHTTPLiveStreaming/UsingHTTPLiveStreaming.html

http://devimages.apple.com/iphone/samples/bipbopgear3.html


On Mon, Jan 10, 2011 at 11:18 AM, Rob Coenen <coenen.rob at gmail.com> wrote:

> Thanks for the update.
> I have been testing with WebKit nightly / 75294 on MacOSX 10.6.6 / 13"
> Macbook Pro, Core Duo.
>
> Here's a test movie that I created a while back. Nevermind the video
> quality- the burned-in timecodes are 100% correct, I have verified this by
> exploring each single frame by hand.
>
>
> http://www.massive-interactive.nl/html5_video/transcoded_03_30_TC_sec_ReviewTest.mp4
>
> Please let me know once you guys have downloaded the file, I like to remove
> it from my el-cheapo hosting account ASAP.
>
> thanks,
>
> Rob
>
>
> On Mon, Jan 10, 2011 at 2:54 PM, Eric Carlson <eric.carlson at apple.com
> >wrote:
>
> >
> > On Jan 9, 2011, at 11:14 AM, Rob Coenen 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?
> >
> >   WebKit's HTMLMediaElement implementation uses different media engines
> on
> > different platforms (eg. QuickTime, QTKit, GStreamer, etc). Each media
> > engine has somewhat different playback characteristics so it is
> impossible
> > to say what you are experiencing without more information. Please file a
> bug
> > report at https://bugs.webkit.org/ with your test page and video file,
> and
> > someone will look into it.
> >
> > eric
> >
> >
>