Check out the image quality of Mozilla's Daala codec right now

Martin Brinkmann
Dec 27, 2014

Daala is the codename for a video compression technology project that Mozilla is working on in collaboration with It is one of many research projects at Mozilla that could shape the future of the Web in significant ways.

Mozilla revealed Daala back in mid-2013 and has been working on the video compression technology ever since.

Mozilla and Xiph published blog posts recently with information about the progress made in 2014.

The team spend time on improving still image coding, the building of tools to evaluate performance against other codecs and video performance in general.

You can test the still image quality of Daala on the Xiph website. There you can compare it with other popular codecs using a slider that you move with your mouse.

You can use the test to compare Daala with JPEG, VP8, VP9, x264, x265 and the original image. The smaller sample image used on the main site is not ideal though and you find the full resolution image and others on this.

While still not perfect, as size information are not provided for example, it is easier to notice differences in quality. There you can also load other test images.

The project team is aware that Daala's quality needs to be improved to surpass HEVC which offers the best quality currently.

Below is a quick demo that characterizes the difference in the codecs. As you move the slider back and forth, especially notice how the details change in the trees, sky, and sand. Daala preserves texture well like JPEG, but doesn't suffer from JPEG's blocking artifacts. VP8 avoids blocking artifacts, but blurs all but the strongest edges and textures. H.264 makes an especially strong showing in this image, though it oversharpens fine edges while losing lower contrast edges and texture. Daala and HEVC are the most visually similar, with consistent treatment of features across the image. HEVC is still the clear winner for now, though that's not to say HEVC is flawless; oddly, it manages to 'trim' the trees shorter in the background! Currently, Daala's primary fault is ringing, which also impacts overall coding efficiency.

The main page holds another interesting option: it allows you to upload an image of your own selection to compare it to the Daala version.

A slider is provided that you can use to change the quality of the Daala image. The size of the resulting image is displayed on the screen as well which you can compare to the size of the original image.

It is unfortunate that source and destination image are not displayed on the screen at the same time as it would make the comparison easier.

Still, it can be used to compare the output size and quality of popular image formats used on today's Internet with the current Daala implementation.

Check out the image quality of Mozilla's Daala codec right now
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Check out the image quality of Mozilla's Daala codec right now
You can test the Daala video compression codec right now to see how well it converts images both size and quality-wise.

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  1. CalBear said on December 29, 2014 at 3:14 pm

    Daala is clearly not as good as JPEG as seen in the bushes along the side of the road. So what is the file size?

    1. Matthew Raymond said on February 16, 2015 at 6:50 pm

      Take a look at the images Pont de Quebec at Night, Buenos Aires and End of Show. Daala might not be as sharp on the high-contrast details, but it’s way better than JPEG for darkness and gradients. JPEG butchers images that have low contrast and subtle shifts in color.

  2. jasray said on December 28, 2014 at 3:57 am

    Wow! All of the coding, math, genius, patience, and whatever else is needed to take a project this far . . . and to continue . . . until an obviously superior rendering occurs makes me shake my head in awe. Since I’m in the field of education, I think, “This is an example of a well-educated mind.” I mean, it’s “perfect.”

  3. ACow said on December 28, 2014 at 3:27 am

    Daala? That’s even worse than gif with a soft g…

    1. Caspy7 said on December 28, 2014 at 6:07 am

      Focusing on the important stuff…

  4. Zeus said on December 28, 2014 at 1:32 am

    The lack of artifacts in the clouds makes me think this would be a really good codec for encoding horror films and other movies with lots of darkness in the fame. Today’s codecs tend to look at a dark room and think, “Hey, time to save a ton of bitrate!” which results in some terribly blocky night scenes.

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