Subject: [Cellar] Hark, a decoder!

From: Derek Buitenhuis <[email-masked]>
Date: Mon, 21 Oct 2019 23:02:55 +0100

So over the last few weeks, I wrote an FFV1 decoder from scatch, in Go,
trying to only reference the spec. Found a fair few spec issues, and
opened bugs for them all.

The idea was rather than make it fast or idiomatic, make it easy to
map parts of it back to the spec (via names and comments).

So, yeah, kinda ugly right, and very much not fast. It does have basic
slice threading, though.

Perhaps of use to some people on here.

Link: https://github.com/dwbuiten/go-ffv1

Please note it only handles version 3 FFV1 files.

Cheers,
- Derek

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From: Kieran O Leary <[email-masked]>
Date: Mon, 21 Oct 2019 23:28:12 +0100

Hi Derek

> opened bugs for them all.

I think this is a fantastic project and it makes me feel like the
specification is (or will be) much more robust after your project. It's
great to know that future decoders could be built from scratch just using
the spec.

> Perhaps of use to some people on here.

I've never really used Go before but I hope to try this out tomorrow on
some of our files.

> Please note it only handles version 3 FFV1 files.

Thanks for this awesome work.

Best,

Kieran O'Leary,

Irish Film Institute

> Cheers,
> - Derek
>
> _______________________________________________
> Cellar mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/cellar
>

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From: Derek Buitenhuis <[email-masked]>
Date: Mon, 21 Oct 2019 23:33:10 +0100

On 21/10/2019 23:28, Kieran O Leary wrote:
> I think this is a fantastic project and it makes me feel like the specification is (or will be) much more robust after your project. It's great to know that future decoders could be built from scratch just using the spec.

Indeed, that was the intent.

> I've never really used Go before but I hope to try this out tomorrow on some of our files.

Note that right now it's just a package with an API; I haven't pushed up a usuable CLI tool yet. It also lacks, for example, some DPX-specific stuff that RAWCooked has, so the color may not be correct for those right now.

Also, maybe bugs. Probably bugs.

Cheers,
- Derek

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From: Michael Richardson <[email-masked]>
Date: Mon, 21 Oct 2019 18:56:35 -0400

> opened bugs for them all.

WOOHOO... more Running Code.
This is a wonderful thing to do!
Thank you for opening the bugs too!

--
Michael Richardson <[email-masked]>, Sandelman Software Works
 -= IPv6 IoT consulting =-

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From: "Peter B." <[email-masked]>
Date: Wed, 23 Oct 2019 17:58:13 +0200

Dear Derek,

Very interesting indeed! :D

How was it to read and interpret the specs?
Anything unclear/missing?

Kind regards,
Peter

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From: Ashley Blewer <[email-masked]>
Date: Thu, 24 Oct 2019 06:13:09 -0400

I am looking forward to Derek speaking about this topic at the upcoming No
Time To Wait conference <https://mediaarea.net/NoTimeToWait4> in early
December. Peter, I know you'll be there so you'll get to see it -- and for
everyone else following along, we offer a livestream of this conference and
videos are added pretty quickly afterwards.

Ashley

On Wed, Oct 23, 2019 at 11:58 AM Peter B. <[email-masked]> wrote:

> > Note that right now it's just a package with an API; I haven't pushed up
> a usuable CLI tool yet. It also lacks, for example, some DPX-specific stuff
> that RAWCooked has, so the color may not be correct for those right now.
> >

---

From: Derek Buitenhuis <[email-masked]>
Date: Fri, 25 Oct 2019 14:54:12 +0100

On 24/10/2019 11:13, Ashley Blewer wrote:
> I am looking forward to Derek speaking about this topic at the upcoming No Time To Wait conference <https://mediaarea.net/NoTimeToWait4> in early December. Peter, I know you'll be there so you'll get to see it -- and for everyone else following along, we offer a livestream of this conference and videos are added pretty quickly afterwards.

This ^

>     Anything unclear/missing?
You can take a gander at the open/closed issues on the FFV1 bug tracker :).

- Derek