Can't render texture with image sequence

[janhenrik_hansen]

We have a problem using an image sequence as a color texture. As soon as I enable Sequence, the texture simply turns light grey. Rendering with interactive, production or vantage all does not work. As soon as you disable sequence you can see the texture again.

Here is the thread in the Rhino forum: https://discourse.mcneel.com/t/image...v-ray-6/158492

Here is a link to the packed project: https://www.dropbox.com/s/04w96yru3r...mated.zip?dl=0

This is very frustrating, since I just want to render a very simple animation where a texture is going through a sequence like a clip playing on an LED screen. :/

Using latest Rhino 8 (but same in latest Rhino 7) and V-Ray 6.00.02.

[seltzdesign]

Really, nobody from Chaos can even confirm or deny this? Is this a bug? All I know its super frustrating, since its the same in Vantage, Interactive Renderer and Production Renderer.

For now we have rendered a sequence in D5 Renderer, where it was literally two clicks to add a video as a texture. We would much rather use V-Ray where we already have all the assets and materials set up properly.


Can someone please see if its a bug specific to us or if its not working in general.

Thanks!

[seltzdesign]

Well, usually not getting an answer straight away means there is something to it. So I am hopeful it will be fixed in a hotfix very soon.

Meanwhile you can see exactly what I mean here: https://recordit.co/tHzCaPHX48

[natalia.gruzdova]

Hello janhenrik_hansen and seltzdesign,
Thank you for the topic and I apologize for the delayed response. You have also opened a ticket to our system and I will post what we have discussed so far regarding rendering image sequence used in Bitmap:

In order to correctly set image sequence it has to be written in the .ifl file format and then loaded into Bitmap. Bitmap does not see .ifl file types by default, but if you type the name or file format .ifl it will be loaded.

Ifl file (image file list) is a text document which contains file names of the corresponding sequence in each line. It can be opened and edited it with Notepad+++ for example.

Important thing to note is that the .ifl file must not contain any numbers in its naming, also the path to the .ifl must not contain any numbers in its name.

Also some kind of animation had to be set in the scene so that image sequence is rendered. (Rhino animation, Bongo, Grasshopper)

Using .ifl will also allow setting properties such as Playback Speed and Type. Without .ifl file images can be loaded as sequence, but these options will not work. These images have to be properly named based on their frame number, e.g. image.0001.png, image.0002.png, etc.

As for the Vantage I will get back to you in the ticket soon.

[seltzdesign]

Edit: We literally typed our responses at the same time, that's why I am repeating what Natalia has said above, which is what she sent me by email yesterday.

----

I got an answer from Chaos regarding this. Turn's out you need to set a .ifl file and not just the first image in a folder of images, like you would expect. Since .ifl is not a valid image format, you cannot select it in the file browser and have to know and type the name manually. The .ifl file and the whole path to the .ifl file cannot contain any number!?

What sadistic developer came up with that "system"? There are many things that are not very intuitive in V-Ray as there are in many other software tools (looking at you, Rhino), but this really takes the crown, because most of this is also not documented at all.

Now I just need to find out how to make it work in Vantage.

[seltzdesign]

What I find almost funny is that in V-Ray if you have selected an .ifl file as an image it actually shows an error saying "file type not allowed: ifl"



I can't think of a reason, why you would not just allow .ifl files if they ARE valid files. Then you could just select the file in the file browser. If Sequence is not enabled you just take the first image from the .ifl file as the image. That way someone might actually work out that this is the way to get an image sequence.

And please someone at Chaos take the 5 minutes it takes to allow numbers in file paths for .ifl files. This limitation does not exist for any other file paths, so why for that? All the numbering for the frames is in the .ifl file, so why can we not have numbers in the path? I don't even understand how that limitation would come about. I also code a lot of tools and we also work with a lot of file paths, but honestly I think it would be harder to include that limitation than to not have that limitation, which is the default. Thinking about it, the order of the frames is all specified in the .ifl files, so you don't even need to consider numbers or sorting order or anything like that. I could have the files use any random file name I want. So why no numbers, when the numbers don't matter at all?

Both as a programmer and UX designer, I am quite honestly astonished.

[natalia.gruzdova]

I am also adding an example scene created with V-Ray 6 and Rhino. Animation here is set to Rhino One-day Sun Animation for test purposes.
Sequence.zip
Here is an example of the .ifl file that can be found in the archive.

[nikolay.bakalov]

Hi,
let me explain about the sadism.

First off the animated image sequence is originally a native 3dsMax feature. It exists in V-Ray in this particular form only because it exists in Max. However in Max the SDK provides the implementation - meaning we ask Max SDK to deliver the image file for the i-th frame, based on the .ifl file, the playback rate and the playback type parameters. At some point the entire logic was ported to the V-Ray core, so that V-Ray for Maya (for example, but others too) can take advantage of the Max .ifl file workflow. And that is how it ended up the Asset Editor.

The issue with the numbers in the file name is a bit unclear, but let me explain. Since you have sequence parameter set to ON, the filename parameter is considered an animated parameter. And thus it should have a frame number placeholder somewhere in the string. Аt render time of the I-th frame, V-Ray simply replaces that number with the current frame number, and then searches for a file with that name. The procedure of finding the frame number placeholder in the name is to run the string from the end, hit the first digit character, and then take all the following (preceding, in fact, since we're running from the end) digits. That segment of the string is labeled frame placeholder and it is replaced with the current frame number (in specific format).
This logic is applied to the entire string, not only to the filename part of it. The reason is because in the VFX industry you may have a whole lot of images for a given frame in a separate folder like 0000, 0001 etc. In this case the folder part is considered frame placeholder.

I agree that there is a potential bug here - since the .ifl by definition contains the per-frame files, it shall not be a subject of per-frame filename modification. However I cannot guarantee that they don't do exactly that in some VFX studio.

So ..
- it is a twisted workflow - agree
- it is because of Max, Maya, and the VFX industry - yes
- we need a better description in the AE - definitely
- we need to throw the whole thing out and rely on smt. else - probably yes. Stay tuned.

[seltzdesign]

In case anyone comes across this and is looking for a tool to make .ifl files easily, here is my tool that I just coded: https://github.com/seltzdesign/simple-ifl-writer

It just takes a folder and writes all the filenames to the .ifl in alphabetical order. Numbers are allowed anywhere in the paths

[konstantin_chaos]

Hi seltzdesign,

Here are some of the things that we can improve when it comes to animated textures:

• We will allow .ifl files to be loaded without any warnings.
• We will look into ways of improving how V-Ray Core handles image sequences. Currently loading an image from a sequence works only for the animation frames that match the image names. Allowing looping and offset should improve things quite a bit.
• If the previous idea doesn't work out, we should be able to handle this at export / render time.
• Additionally we'll talk to the Vantage team to see which setup would work best in Vantage.

Regards,
Konstantin

[seltzdesign]

Hi seltzdesign,

Here are some of the things that we can improve when it comes to animated textures:

• We will allow .ifl files to be loaded without any warnings.
• We will look into ways of improving how V-Ray Core handles image sequences. Currently loading an image from a sequence works only for the animation frames that match the image names. Allowing looping and offset should improve things quite a bit.
• If the previous idea doesn't work out, we should be able to handle this at export / render time.
• Additionally we'll talk to the Vantage team to see which setup would work best in Vantage.

Regards,
Konstantin

Thanks konstantin_chaos, for acknowledging some areas for improvement.

But actually you just dropped another undocumented hint "Currently loading an image from a sequence works only for the animation frames that match the image names". That wasn't mentioned anywhere so far. One of the image sequences I was trying had its numbering start at the frame in the video, which was something like 486 and not 0. Do you mean the frame in the Vantage animation or the frame in the animation in the host application though?

I tried using https://forums.chaos.com/forum/chaos...05#post1159505 the method outlined here by Peter.Chaushev from scratch, but that also didn't work. I sent natalia.gruzdova a screen recording of me trying it, but for the life of me I cannot figure out what else to try.

[Micha]

I've been reacquainting myself with sequencing for a long time and opened an old project file where I had used sequencing before. It still works, but only in slow CPU mode. Is the GPU mode not supported? Isn't it just a matter of loading one image file at a time?

[Micha]

I found now animated textures should work in GPU mode, since it works for textured lights. I can project a sequence. I will start a new thread with a bug report.

[seltzdesign]

Yeah, that also struck me as very strange, that it would not work in GPU mode. I ended up rendering in Vantage, which was also quite a journey to get it to work. I think the image sequence stuff is not used very much, so documentation is not great. I found out so many odd things from the devs that are undocumented. I still wish they would just let us add a Movie file like in D5 render.

[seltzdesign]

I think the image sequence rendering should also be mentioned in these CPU vs GPU capabilities comparison pages: https://docs.chaos.com/display/VRHIN...ering+Features, but they are not mentioned at all.