[daala] I tried out Daala, my findings

[Thomas Szymczak]

Hello, everyone!

Yesterday I downloaded and compiled the Daala codec and used it to encode and
play back a few videos. The quality of the videos isn't very good, even compared
to Theora at about the same bitrate. I didn't expect great quality, as Daala is
still in its infancy. I'd like to bring a few bugs to the developers' attention,
but you may already be aware of these issues and/or you might plan on fixing
them later.


1. If you run "encoder_example --help" there is a typo. It says 'Frequence'
instead of 'Frequency'. I would also prefer that the help text look more like a
man page, but this is more about taste than functionality. Furthermore, it
doesn't document the --enable-encoder-check option.

The help text is located within the source tree at examples/encoder_example.c
starting at line 368. I made a patch to fix this, but it still doesn't document
the --enable-encoder-check option. I ran the patched code, and it worked, but
I'm not sure if I made the patch correctly. I'm not a programmer and this is the
first time I've ever contributed code to a project. If you don't like the
patch, I'm not urging you to use it.


2. The -V option in the encoder doesn't seem to affect the target bitrate as
stated in the output of the --help option. It produces a really large
(lossless?) file instead. Here are some steps to reproduce:

1. For an input, I used video I had recorded with my camera and converted to the
yuv4mpeg format. I also downloaded
http://media.xiph.org/video/derf/y4m/akiyo_cif.y4m and got the same results.
2. Run:
encoder_example -V 500 -o akiyo_cif-daala.ogv ./akiyo_cif.y4m
3. You should get a file that is 22.0 Megabytes in size, instead of about 625
kilobytes, which should be the approximate size of a 10-second video at
500 kbps.

This occurred with the version from January 17, on my machine which runs Linux
Mint 13. I am experienced with Linux and can give you more information if
necessary.


There are other issues as well, but I assume that these are just due to missing
features rather than bugs and they will get ironed out later: The video player
seems to play back videos as fast as possible instead of at the right rate (So
that a 1-minute video might play in 40 seconds, etc). The encoder is slow, and
incredibly slow when using intra prediction.

To all the developers, thank you for working so hard on this project. I'm very
glad you're doing this work and I'm very glad to assist you.
 		 	   		  
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