How to convert a video to ogg with VLC

With VideoLan VLC media player you can convert almost any video to a Theora-Vorbis ogg file, that you can use with Pogg.

You can download VLC from http://www.videolan.org/vlc/

To convert a video go to Media→Convert/Save…

Click on the Add… button and select the file you want to convert. Then click on the Convert/Save button.

Click on Browse and write the file name of the new ogg video.

Then you have to select the Profile. You can select “Video - Theora + Vorbis (OGG)” which will create an ogg file with 800 kb/s Theora and 128 kb/s stereo Vorbis. With these parameters one minute of video will be (800+128)/8*60= 7MB.

If you want to control the size of the file, you can create a new Profile.

To create a new profile, click on the third button (with the list and the yellow star).

Write a name for you profile and select the Ogg/Ogm encapsulation.

Select the Video codec tab. Check Video and select the Theora Codec. The Bitrate is the parameter to control the size of the file and quality of the video. For a video of 320×240 pixels, 512 kb/s is a good quality. It seems that for 320×240 pixels the minimum bit rate is about 300kb/s, which gives a pretty good quality. If you try to encode to a lower bit rate, it will encode the video with 300kb/s anyway. This minimum bit rate is proportional to the area (number of pixels) of the video. If you need a smaller bit rate you can resize the image with the Scale parameter. A scale of 0.5 will resize a video of 320×240 to 160×120, which you can compress to about 75kb/s (a scale of 0.5 reduces the area to a 25% so you can reduce the bit rate to a 25%).

My rule of thumb is as follows: multiply the width by the height to get the area in pixels. If you want good quality, divide the area by 150. If you want the minimum size (and lower quality), divide it by 256. If you need a lower bit rate, scale the image and the area and bitrates will be smaller. Examples:

• 320×240 = 76800 (area). Then good quality is 76800/150=512kb/s and the minimum bitrate that VLC will encode is about 76800/256=300kp/s.
• 160×120 = 19200. Good quality = 19200/150 = 128kb/s. Minimum = 19200/256 = 75kb/s.

Now select the Audio codec tab. If you want a video with sound, select the Audio checkbox, the Vorbis codec and the rest of parameters. If you don't need a stereo file, select only 1 channel. For better audio quality select 128kb/s and Sample Rate = 44100 (this is CD quality). If you don't need a good sound quality and you want a small file, select Sample Rate = 11250 and 16kb/s (this is telephone quality).

It seems that the minimum bit rate for Vorbis (in VLC) is 16kbps. If you try to make it smaller than that, you will get a file without sound.

Finally click Save to save your profile.

Now we can select our new Profile and click on Start to start encoding.

Wait for the conversion and open the file you just created to check if it looks and sounds good.

You can check that the file is really an ogg Theora-Vorbis in Tools→Codec Information

There should be a stream with Codec: theo and another stream with Codec: vorb

If the quality is too bad or you need a smaller file size, repeat all the steps changing the codec parameters.