[FIX ]Captions fail to extract on HEVC video stream #1690

[trufio465-bot]

[FIX]

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This PR fixes an issue where CCExtractor failed to extract EIA-608 captions from HEVC (H.265) transport streams.

Problem:
CCExtractor's transport stream parser did not recognize HEVC (stream type 0x24) as a valid video stream type capable of carrying embedded captions. This resulted in "No captions were found in input" for HEVC files, even when captions were present and playable in other media players.

Solution:
Comprehensive HEVC support has been added across the codebase:

1. Defined CCX_STREAM_TYPE_VIDEO_HEVC (0x24) and CCX_HEVC buffer type.
2. Updated the TS parser to recognize HEVC streams during PMT processing and caption detection.
3. Integrated HEVC streams into the existing AVC (H.264) caption processing pipeline, as both use similar SEI mechanisms for caption embedding.
4. Ensured HEVC streams are correctly handled in stream information, buffer management, and sequencing logic.
5. Updated Rust bindings for consistency.

Impact:
CCExtractor can now successfully detect and extract EIA-608 captions from HEVC transport stream files.

[ccextractor-bot]

CCExtractor CI platform finished running the test files on windows. Below is a summary of the test results, when compared to test for commit a34ba0f...:

Report Name	Tests Passed
Broken	13/13
CEA-708	13/14
DVB	4/7
DVD	3/3
DVR-MS	2/2
General	27/27
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	86/86
Teletext	21/21
WTV	10/13
XDS	34/34

Your PR breaks these cases:

• ccextractor --service 1 --out=txt f17524b53f...

NOTE: The following tests have been failing on the master branch as well as the PR:

• ccextractor --stdout --quiet --no-fontcolor 79a51f3500..., Last passed:

  Never

• ccextractor --stdout --quiet --no-fontcolor 767b546f96..., Last passed:

  Never

• ccextractor --autoprogram --out=srt --latin1 --quant 0 85271be4d2..., Last passed:

  Never

• ccextractor --out=srt --latin1 f23a544ba8..., Last passed:

  Never

• ccextractor --out=srt --latin1 10f0f77cf4..., Last passed:

  Test 5993

• ccextractor --out=srt --latin1 df3b4d62d3..., Last passed:

  Never

It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you).

Check the result page for more info.