[daala] I tried out Daala, my findings

[Tristan Matthews]

Hi Thomas,

On Mon, Jan 20, 2014 at 4:30 PM, Thomas Szymczak <thomasthekitty at hotmail.com
> wrote:

> 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.
>

The "--enable-encoder-check" option is set at configure-time (see
./configure --help), not run-time.


> 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.
>

-- 
Tristan Matthews
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