title: Transcoding, Formats & Codecs
---
+<h2>Video Formats and Codecs</h2>
<p>
A short primer on video-files, formats and codecs – because it is often cause for confusion:
</p>
</p>
<p>
-How these tracks are stored in the file is defined by the <strong>file-format</strong>. Common formats are avi, mov, ogg, mkv, mpeg, mpeg-ts, mp4, flv, vob
+How these tracks are stored in the file is defined by the <em>file-format</em>. Common formats are avi, mov, ogg, mkv, mpeg, mpeg-ts, mp4, flv, vob
</p>
<p>
-Each of the tracks by itself in <em>encoded</em> - using a Codec. Common Video-Codecs are h264, mpeg2, mpeg4, theora, mjpeg, wmv3. Audio-Codecs: mp2, mp3, dts, aac, wav/pcm.
+Each of the tracks by itself in <em>encoded</em> - using a <abbr title="Coder-Decoder">Codec</abbr>. Common Video-Codecs are h264, mpeg2, mpeg4, theora, mjpeg, wmv3. Audio-Codecs: mp2, mp3, dts, aac, wav/pcm.
</p>
<p>
-Not all codecs can be packed into a given format. For example the 'mpeg' format is limited to mpeg2, mpeg4 and mp3 codecs (not entirely true) and generally naming conventions uses for format and codecs are cause for a lot of confusion. DVDs do have stringent limitations…
+Not all codecs can be packed into a given format. For example the 'mpeg' format is limited to mpeg2, mpeg4 and mp3 codecs (not entirely true). DVDs do have stringent limitations as well. The opposite would be .avi; pretty much every audio/video codec combination can be contained in an avi file-format.
</p>
<p>
-The export dialog includes presets for common format & codec combinations (such as DVD, web-video,..). If in doubt use one of the presets.
+To make things worse, naming conventions for video codecs and formats are often identical (esp mpeg ones) which leads to confusion.
+All in all it is a very wide and deep field. Suffice there are different uses for different codecs and formats.
+</p>
+
+<h2>Ardour specific</h2>
+
+<p>
+Ardour supports a wide variety of video file-formats and video-codecs. More specifically, Ardour itself actually does not support any video at all but delegates handling of video files to <a href="http://ffmpeg.org">ffmpeg</a> which supports over 350 different video-codecs and more than 250 file-formats.
</p>
<p>
-All in all it is a very wide and deep field. Suffice there are different uses for different codecs.
-When importing a video into ardour, it will be <em>transcoded</em> (transcoding: change from one format and codec to another) to avi/mjpeg for internal use (this allows reliable seeking to frames at low CPU cost - the file-size will increase, but hard-disks are large and fast).
+When importing a video into Ardour, it will be <em>transcoded</em> (transcoding: change from one format and codec to another) to avi/mjpeg for internal use (this allows reliable seeking to frames at low CPU cost - the file-size will increase, but hard-disks are large and fast).
+</p>
+
+<p>
+The export dialog includes presets for common format & codec combinations (such as DVD, web-video,..). If in doubt use one of the presets.
</p>
<p>
-As last note: Every time a video is transcoded the quality gets worse. Hence for the final mastering/muxing process always to back to the original source of the video.
+As last note: Every time a video is transcoded the quality can only get worse. Hence for the final mastering/<abbr title="Multiplexing Audio and Video">muxing</abbr> process, one should always to back and use the original source of the video.
</p>