Blogging Theora

[xiphmont]

It's time for the latest Thusnelda encoder project update summary!

Although I haven't gotten much time to dive back into Thusnelda coding myself, Tim Terriberry, Greg Maxwell and others have continued the work along at a merry pace. In the past few weeks, they've finally replaced the leaky fDCT from the original VP3 and begun work on adjusting the main quantization matrices and, hopefully soon, adaptive quantization. These improvements all improve fine detail rendering and, somewhat unexpectedly, improve gradient rendering as well:

The screen caps above were produced by Theora 1.0 on the left and an experimental version of Thusnelda with early quant matrix optimization work in addition to the new fDCT on the right. Both clips were encoded in constant-quantizer mode and equal bitrates.

Other improvements, more details and the full update report here.

Comments

Re: Problem with older ffmpeg, not ffmpeg2theora

[(Anonymous)]

By that metric, ffmpeg is also sabotaging MPEG4: the defaults are terrible and it's difficult to configure it well (this is both for its own internal ASP encoder, and for libx264 for AVC). Most videos I've seen encoded in these formats suffer quite a bit quality-wise.

OTOH, that "terrible ogg support" is probably the reason Google Chrome supports Theora+Vorbis (in addition to h.264+AAC), and I can tell you both work as well/bad as each other - for instance seeking and A/V sync do work (albeit seeking is a bit slower, it's probably suffering from the "binary search over the network" syndrome, just as Firefox did...)

Frankly this mutual hate seems overblown.