Options

The following global options are mapped to internal libtheora options which affect the quality and the bitrate of the encoded stream.

'b'

Set the video bitrate in bit/s for CBR (Constant Bit Rate) mode. In case VBR (Variable Bit Rate) mode is enabled this option is ignored.

'flags'

Used to enable constant quality mode (VBR) encoding through the 'qscale' flag, and to enable the pass1 and pass2 modes.

'g'

Set the GOP size.

'global_quality'

Set the global quality as an integer in lambda units.

Only relevant when VBR mode is enabled with flags +qscale. The value is converted to QP units by dividing it by FF_QP2LAMBDA, clipped in the [0 - 10] range, and then multiplied by 6.3 to get a value in the native libtheora range [0-63]. A higher value corresponds to a higher quality.

'q'

Enable VBR mode when set to a non-negative value, and set constant quality value as a double floating point value in QP units.

The value is clipped in the [0-10] range, and then multiplied by 6.3 to get a value in the native libtheora range [0-63].

This option is valid only using the ffmpeg command-line tool. For library interface users, use 'global_quality'.