Using Stable Diffision models for Colorization

[Dan64]

Attaching the workflow to the image isn't a bizarre idea of mine. It's the standard way the images are saved by ComfyUI. 
The reason is simple: anyone receiving an image generated by ComfyUI can see how it was generated and possibly reproduce the same result. 

I downloaded the image from the forum and uploaded it to ComfyUI as described, and the workflow is perfectly visible. 

However, I attached a zip file containing the workflow in json format. Again, just upload the file to ComfyUI using drag-and-drop to see the workflow. 

I included also a legend with the links where is possible to download the models used in the workflow.

Dan

[Selur]

Unlike dragging&dropping the png, it works for the json for me.
¯\_(ツ)_/¯

Cu Selur

[Dan64]

In the case it could be useful, in the workflow was used the model svdq-fp4 available at this page: https://huggingface.co/nunchaku-ai/nunch...-edit-2509
The fp4 quantization is supported only by GPU RTX50, for older GPU it is necessary to use svdq-int4 quantization, you can find it on the link above.

Some suggestions: given that the colorization of a B&W images is a much simpler task, respect the text to image. 
It is possible to use the rank32 version of svdq-int4 quantization and lower the number of steps from 4 to 2.

Dan

[Dan64]

Hello,

  For those interested in applying DiT models to color old BW films, I've recolored the films I've published on the Internet Archive using the new Pipeline, which uses a DiT model to automatically color the reference frames. 
  The list is available at this link: havc-colorized-movies

  the new Pipeline for colorize the movies is the following:

    1) extract the reference frames (with HAVC)
    2) colorize the reference frames with a DiT model (currently I'm using qwen-image-edit) 
    3) propagate the color of reference frames to full clip  (with HAVC)
    4) generate an alternative stable colored clip  (with HAVC)  

 unfortunately even if the frames colored with DiT models have more stable and better colors than DDColor, the problem of color stability and consistency is still present. In order to mitigate it, I need to merge the clip colored at the step 3 with the clip generated at step 4.
   In my list of colored movies, there is only one movie that was not merged with an alternative stable colored clip: a-night-to-remember-colorized-1958-720p (*)

Dan

(*) left as a reference to the problems of stability and consistency of colors using DiT models. The movie was colored with HAVC(ColorMNet, max_memory_frames=150), despite its shortcomings, ColorMNet is the only model that is able to mitigate this problem automatically.