PGS sample that uses cropping?

cubicibo · 30th October 2022, 17:08

I am looking for a SUP sample file that use the PGS cropping functionality. Simple as that.

I tried to mimick the description in the PGS patent and BDAV patent but I cannot get it to work at all. Is it even part of the Blu-Ray specs nowadays?

There must be at least one sample around, because the FFmpeg developers are aware that the flag mask is 0x80 (while the forced one is masked with 0x40).

wswartzendruber · 23rd November 2022, 16:41

If anyone has a professionally-produced sample, I'll take a copy as well. I've got a PGS library that I maintain. The best I've come up with for testing cropped windows is synthetic unit tests, but no real-world samples.

cubicibo: If you want to mess with Rust, that library should be correct about generating such window definition segments.

On the other hand, I imagine everyone sees that only the simplest uses of PGS serve any real purpose. It shouldn't be so surprising that part of it would be omitted from whatever production specification is in effect.

cubicibo · 23rd November 2022, 18:14

I do not know how to program in RUST. if you can produce an attempt that mimics the patent drawings 15 (scrolling) or 16 (wipe-out) that also passes your unit tests, I'll check it on real hardware. I failed to reproduce both. I did get my playback device to start the wipe-in on a sample I produced but it always crashed within one or two pixels in. Object was displayed at the wrong location too. But in most of the time the decoder was crashing before anything would show on screen.

wswartzendruber · 24th November 2022, 16:25

If I may, the patent is not authoritative. I can make that assertion because it doesn't deal with forced subtitles in a manner compatible with commercial implementations.

cubicibo · 24th November 2022, 16:56

But forced subtitles are just done using an additional flag not described in the original patent? If a PGS decoder is too old to decode the forced flag, it is ignored and the PCS is decoded normally. There are no fewer or additional data fields inserted whatever the flag is decoded or not, unlike cropping.

wswartzendruber · 30th November 2022, 16:25

I suppose that depends on if you're masking against the flags field, or parsing its value outright.

You have a point.

30th October 2022, 17:08	#1 \| Link
cubicibo Registered User Join Date: Feb 2022 Posts: 28	PGS sample that uses cropping? I am looking for a SUP sample file that use the PGS cropping functionality. Simple as that. I tried to mimick the description in the PGS patent and BDAV patent but I cannot get it to work at all. Is it even part of the Blu-Ray specs nowadays? There must be at least one sample around, because the FFmpeg developers are aware that the flag mask is 0x80 (while the forced one is masked with 0x40).

23rd November 2022, 16:41	#2 \| Link
wswartzendruber hlg-tools Maintainer Join Date: Feb 2008 Posts: 345	If anyone has a professionally-produced sample, I'll take a copy as well. I've got a PGS library that I maintain. The best I've come up with for testing cropped windows is synthetic unit tests, but no real-world samples. cubicibo: If you want to mess with Rust, that library should be correct about generating such window definition segments. On the other hand, I imagine everyone sees that only the simplest uses of PGS serve any real purpose. It shouldn't be so surprising that part of it would be omitted from whatever production specification is in effect. Last edited by wswartzendruber; 23rd November 2022 at 16:45.

23rd November 2022, 18:14	#3 \| Link
cubicibo Registered User Join Date: Feb 2022 Posts: 28	I do not know how to program in RUST. if you can produce an attempt that mimics the patent drawings 15 (scrolling) or 16 (wipe-out) that also passes your unit tests, I'll check it on real hardware. I failed to reproduce both. I did get my playback device to start the wipe-in on a sample I produced but it always crashed within one or two pixels in. Object was displayed at the wrong location too. But in most of the time the decoder was crashing before anything would show on screen. Last edited by cubicibo; 23rd November 2022 at 18:18.

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24th November 2022, 16:25	#4 \| Link
wswartzendruber hlg-tools Maintainer Join Date: Feb 2008 Posts: 345	If I may, the patent is not authoritative. I can make that assertion because it doesn't deal with forced subtitles in a manner compatible with commercial implementations.

24th November 2022, 16:56	#5 \| Link
cubicibo Registered User Join Date: Feb 2022 Posts: 28	But forced subtitles are just done using an additional flag not described in the original patent? If a PGS decoder is too old to decode the forced flag, it is ignored and the PCS is decoded normally. There are no fewer or additional data fields inserted whatever the flag is decoded or not, unlike cropping.

30th November 2022, 16:25	#6 \| Link
wswartzendruber hlg-tools Maintainer Join Date: Feb 2008 Posts: 345	I suppose that depends on if you're masking against the flags field, or parsing its value outright. You have a point.