Playback Troubleshooting

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We'd like to hear detailed descriptions of problems viewing videos in standalone players and browsers. HTML5 and WebM especially are very new, and it's highly unlikely the experience in any browser is going to be free of hiccups quite yet. The more feedback we get about what doesn't work, the more we can do to make sure problems get fixed.

If you don't see your browser or player below, feel free to add it to the appropriate list. And to avoid any battles over natural pecking order, keep them in alphabetical order ;-)

A list of Ogg Theora players (without troubleshooting or discussion) with links to vendor pages can be found on the Theora Software Players page.

Contents

In-browser Playback

Hiccups not specific to any browser

Brief flash of beginning of video when changing resolutions

There are two basic ways of changing the video currently playing back in the current HTML5 spec, and both have some practical problems we'd like to see fixed before the spec is finalized.

The first way to change streams is to create a new video element via javascript, wait for it to load, then replace the current video with the new one. Unfortunately, HTML5 gives no way to prevent the original video, even when stopped, from using all available bandwidth to keep buffering as fast as it can. This starves the replacement video of network access, causing a lengthy delay when loading. It looks very nice and seamless when it finally works, but can easily result is switching video streams taking 15-30 seconds or more.

The second option is to switch the preexisting video element to a new stream. This is much faster as the original stream stops sinking bandwidth immediately, but upon loading it always starts from the beginning and in current browsers also displays the first frame, even if playback isn't started. After the load completes, then it's possible to seek forward to where the original stream started. It doesn't look as good, but it's much faster in practice.

Xiph's video playback scripting uses the second, faster option, so there's a brief flash back to the beginning of the video upon resolution switch.

No 'extra' controls [resolution switching, chapter navigation] on some browsers

The 'extra controls' that appear as a bar along the top of the video playback window are implemented using HTML5 <video> tag features, and as such can't work as written in browsers using the Cortado fallback applet. Cortado does support subtitles via the 'CC' button in the lower right of the playback area, and our Ogg streams include subtitle tracks.

Firefox

Search for known Firefox Audio/Video bugs

Firefox before Version 1.x,2.x,3.0.x

Firefox before version 3.5 (or 3.1 beta) did not include native support for Ogg or WebM. These broswers can play Ogg video via the Cortado applet if a Java runtime enviroment is installed. With Java installed, playback is seamless but does not have a full set of HTML5 features; resolution switching and chapter navigation are disabled. Cortado has native support for Ogg Kate subtitles.

Firefox 3.5.x

Firefox 3.5 was the first version of Firefox to ship with native Ogg playback. It features a full HTML5 feature set, though it is known to be relatively slow about seeking and navigation.

Seeking may work poorly if your connectivity to the media passes through a proxy which strips HTTP range requests.

On common GNU/Linux systems with pulseaudio, such as Ubuntu and Fedora, playback will halt and refuse to continue after pausing (and potentially seeking) and will not continue unless the page is completely reloaded due to Mozilla Bug#526411.

Firefox 3.6.x

Firefox 3.6 behaves similarly to FF3.5, but adds poster support and more robust Ogg stream navigation along with some bug fixes.

Seeking may work poorly if your connectivity to the media passes through a proxy which strips HTTP range requests.

Firefox 4.0 (currently in beta)

Firefox 4.0 features a new Ogg playback engine that allows considerably faster stream navigation, as well as WebM support.

Google Chrome

Search for video bugs in Chrome's bugtracker

Google Chrome added Ogg playback support in version [?], but it known to have serious bugs when seeking in Ogg streams; it also tends to lose the beginning of videos. Recent releases of Chrome support WebM, which works considerably better, though the playback framerate is often choppy/jerky (at least on Linux).

Internet Explorer

Internet explorer 5, 6, 7, 8

Internet Explorer through version 8 has no support whatsoever for Ogg, WebM or the video tag. Normal installs do include Java support, however, so these browsers are able to play Ogg video through the Cortado applet. With Cortado, playback is seamless but does not have a full set of HTML5 features; resolution switching and chapter navigation are disabled. Cortado has native support for Ogg Kate subtitles.

Internet Explorer 9

Internet Explorer 9 (currently in alpha/beta) apparently at least somewhat supports the HTML 5 video tag, however it does not support Ogg or WebM playback out of the box. Microsoft has stated it will support Ogg and WebM 'if the codecs are installed on the system'. Presumably having the Open Codecs pack installed fufills this requirement and enables Ogg and WebM support (confimation would be appreciated! If you have the Open Codecs Directshow filters installed, you should get full in-browser playback).

Internet Explorer 9 without Ogg/WebM support installed can presumably still play back Ogg video via the Cortado applet as in versions 8 and earlier (again, confimation would be appreciated!)

Opera

Opera long supported Ogg playback in developer builds, and finally shipped native Ogg support in release 10.5. As of 10.60, WebM is also natively supported.

Netscape Navigator

Cortado ns4.png

Laugh if you must, but Navigator back to version 4 can play Ogg video via the Cortado applet.


Safari

Safari does not ship native support for Ogg or WebM video, however all versions can play Ogg video via the Cortado applet. With Cortado, playback is seamless but does not have a full set of HTML5 features; resolution switching and chapter navigation are disabled. Cortado has native support for Ogg Kate subtitles.

As of Safari 3.1, Safari supports full HTML5 Ogg video playback via the XiphQT Quicktime Components.

Standalone Players and Tools

Core Player

FFMPEG / ffplay

As of release 0.6, ffmpeg supports WebM playback, and Ogg playback is solid with the exception of surround support (eg 5.1 and other surround encodings produced my modern Vorbis encoders will not play).

Prior to ffmpeg 0.6, WebM was not supported and Ogg video playback was broken due to a number of longstanding bugs caused by treating Theora as if it was just VP3 (eg, the 'sheet lightning acid trip' bug that caused the image to disintegrate into a shower of colored blocks). Many applications and video sharing sites (such as YouTube) are still using old versions of ffmpeg internally, and as such, they cannot handle Ogg video unless it is encoded in 'vp3 compatability mode'.

Media Player Classic

Mplayer

Recent mplayer versions have good natives Ogg playback support and can handle WebM playback through libavcodec (ffmpeg libraries).

Mplayer has had a number of minor Ogg playback bugs in the past that mostly caused seeking or smoothness hiccups. Recent versions should have fixed all of the playback/seeking bugs of note.

Helix Player (Real)

Quicktime

Quicktime supports Ogg and WebM playback and encoding through the XiphQT Quicktime Components. These components also add Ogg support to Quicktime-aware applications such as Final Cut and Final Cut Pro.

Totem

Totem supports Ogg and WebM playback via native support in gstreamer.

Whoops--- we added French subtitles to the Ogg streams and gstreamer broke. Badly. Apparently it can't handle both subtitles in the same stream, we'll consider removing the subs for now... --Monty

VLC

VLC has had good native Ogg support since the GoldenEye release. Webm support is available in 1.1+.

Windows Media Player

WMP supports Ogg and WebM playback through the Open Codecs DirectShow filter pack.

Xine

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