Hap Alpha

[laygir]

Hello,

As I was having some test renders to see how Hap Alpha performs I've encountered some artifacts alogn the edge lines.

I have attached a closeup of a graphic with alpha channel. You may see the red artifacts on both transparent background and with added a white background. Any workaround?

Thanks!

[bangnoise]

Hi - can you provide a single source frame with alpha as png - ie before rendering to Hap.

[laygir]

Helo.

This is the exact frame from the source. It's actually a shape animation in After Effects comp.

I've tried:
rendering directly to hap alpha
rendering directly animation alpha and then hap alpha
converting rendered animation alpha to hap alpha through mpeg stream clip

but no luck.

• as the shape is white, it just blended to the web site. it is there.

[bangnoise]

I can't reproduce this - can you give step by step instructions to reproduce the problem using the image you provided above, including steps to observe the problem.

[laygir]

Hi! Thanks for the help!

1. Create a comp in After Effects ( 800 x 800px)
2. Draw a white solid 200x200 px
3. Rotate the solid, for example 33 degrees.
4. From the top menu; Composition > Add to Render Queue
5. Choose RGB + Alpha from the Output Module
6. Choose Hap Alpha from Format Options
7. Render the file
8. Now as we have a video file with hap alpha codec, import it back to
   After Effects
9. Create a new comp 800 x 800px
10. Put in the video file just rendered in to this comp.
11. Create a new white solid 800 x 800 px
12. Set this white background solid beneath the rendered layer.
13. now we have a video and white solid on top. and we can see the edge
    artifacts.

Özgür Atmaca

On Wed, Apr 15, 2015 at 12:54 PM, Tom Butterworth notifications@github.com
wrote:

I can't reproduce this - can you give step by step instructions to
reproduce the problem using the image you provided above, including steps
to observe the problem.

[image: 15 04 15-main output-10 48 12]
https://cloud.githubusercontent.com/assets/1694058/7156333/944903de-e35d-11e4-98ad-ff096c3cc5a9.png

—
Reply to this email directly or view it on GitHub
#8 (comment).

[laygir]

[laygir]

The black background is actually After Effects's composition background. When you like to render with alpha channel, it doesn't include this black composition background.

But if any case you like to change this background color to something else, this can be done through the compositon settings > background color in the bottom.

If you change this to something else like red. and when you do the whole process again, you will see red artifacts around edges.

[laygir]

Hello, do you have any resolution on your side?

Cheers!

[bangnoise]

I haven't had a chance to look at this yet. In the mean time, avoid importing rendered Hap into AE - it's going to be a lossy process anyway.

[bentoncbainbridge]

Tom, I have an idea about this if you are still working on the noisy edges
Benton
On Apr 21, 2015 11:06 AM, "Tom Butterworth" notifications@github.com
wrote:

I haven't had a chance to look at this yet. In the mean time, avoid
importing rendered Hap into AE - it's going to be a lossy process anyway.

Reply to this email directly or view it on GitHub
#8 (comment).

[bangnoise]

@bentoncbainbridge as I say, I haven't even looked at this yet. Any ideas gratefully received.

[bentoncbainbridge]

@laygir if you can upload your AfterEffects project to a Google Drive, or
just email it to me directly, I will look at it. As Tom says, do not
reimport the compressed Hap Alpha into an AE project and then re-export.
Use "Animation" or "uncompressed" for all outputs until the final render.

Tom, I have an idea about how to keep the alpha clean, would rather PM with
you when you have the chance.

Benton

Benton C Bainbridge
+1.646.338.9172
bentoncbainbridge.com
bentoncbainbridge@gmail.com

On Sat, Apr 25, 2015 at 11:44 AM, Tom Butterworth notifications@github.com
wrote:

@bentoncbainbridge https://github.com/bentoncbainbridge as I say, I
haven't even looked at this yet. Any ideas gratefully received.

Reply to this email directly or view it on GitHub
#8 (comment).

[bangnoise]

closing this, if you still have encoding errors please open issues with the codec you are using (not this repo, which is for the Hap specification).