Python method xbmc.getCacheThumbName deprecated/broken

[scott967]

Bug report

Describe the bug

Here is a clear and concise description of what the problem is:

A call to xbmc.getCacheThumbName returns unusable result. An inspection of code shows:

xbmc/xbmc/interfaces/legacy/ModuleXbmc.cpp

Lines 382 to 387 in 8e01076

	String getCacheThumbName(const String& path)
	{
	XBMC_TRACE;
	auto crc = Crc32::ComputeFromLowerCase(path);
	return StringUtils::Format("{:08x}.tbn", crc);
	}

which seems to be old code. Seems to have last been touched in 2016 #10107

In doing some searches, have seen various dev/support threads on this; don't think it works and the most useful solution is work around of using JSON-RPC instead.

Expected Behavior

Here is a clear and concise description of what was expected to happen:

When calling xbmc.getCacheThumbName with a video or audio thumb -- image://video@path/filename/ as obtained from the videodb should get a valid subfolder/filename from the Thumbnails folder.

Example: library has movie C:\Test movie\Easter Parade\Easter Parade (1948).mkv
Kodi generates thumbnail and videodb and updates art table image://video@C%3a%5cTest%20movie%5cEaster%20Parade%5cEaster%20Parade%20(1948).mkv/

texturesdb texture table for that url has cachedurl of 6/6c841ad1.jpg and that cached image does exist.

xbmc.getCacheThumbName returns 27ef574a.tbn which is consistent with the code.

Actual Behavior

An invalid image path/filename is returned 27ef574a.tbn It appears the intent of the method is just to compute a hash; not get the actual cached filename from Thumbnails. I tried various permutations on the url (deleting "image://" , trailing "/", etc but couldn't get the right cache filename (disregarding the old .tbn extension)
Reviewing TextureCache.cpp, I wasn't able to figure out the correct way to compute the cache filename.

Possible Fix

To Reproduce

Steps to reproduce the behavior:

1. get a video thumb from the videodb
2. in python, pass the result as arg to xbmc.getCacheThumbName
3. log the return from function

Debuglog

The debuglog can be found here:
https://paste.kodi.tv/dukazavasi.kodi

Screenshots

Here are some links or screenshots to help explain the problem:

Additional context or screenshots (if appropriate)

Here is some additional context or explanation that might help:

Your Environment

Used Operating system:

• Android

• iOS

• tvOS

• Linux

• macOS

• Windows

• Windows UWP

• Operating system version/name: Win 10 x64

• Kodi version: 20 RC1 win x64

note: Once the issue is made we require you to update it with new information or Kodi versions should that be required.
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[scott967]

After additional testing it appears that the right way to call xbmc.getCacheThumbName is to use the raw uri and not decode or otherwise clean it up, so format like:
image://video@C%3a%5cTest%20movie%5cThe%20Admiral%20Roaring%20Currents%20(2004)%5cThe%20Admiral%20Roaring%20Currents%20(2004).mkv/

will generate a good filename, but the .tbn extension should be changed to .jpg I think. Suggest also the doxygen documentation provide some more clarity as to the argument format.

[sarbes]

I would like to reserve the right to have other (GPU specific) formats in the future.

If someone would change this, please consider not hard coding the file extension.