[PR #1869] [MERGED] feat(wtv): Add DVB teletext stream detection in WTV files #2643

New Issue

claunia · 2026-01-29T17:23:15Z

claunia commented

2026-01-29 17:23:15 +00:00

📋 Pull Request Information

Original PR: https://github.com/CCExtractor/ccextractor/pull/1869
Author: @cfsmp3
Created: 12/20/2025
Status: ✅ Merged
Merged: 12/21/2025
Merged by: @cfsmp3

Base: master ← Head: fix/wtv-teletext-detection-1391

📝 Commits (2)

e87807e feat(wtv): Add DVB teletext stream detection in WTV files
60cec9e style: Fix clang-format indentation

📊 Changes

2 files changed (+102 additions, -4 deletions)

View changed files

📝 src/lib_ccx/wtv_constants.h (+2 -0)
📝 src/lib_ccx/wtv_functions.c (+100 -4)

📄 Description

Summary

Adds detection of DVB teletext streams in WTV (Windows TV) files
Previously, teletext streams were silently ignored, producing empty output files

Changes

Add WTV_STREAM_TELETEXT GUID to recognize DVB teletext streams
Detect teletext by examining format subtype GUID at offset 0x4C in MSTVCAPTION metadata
Initialize teletext decoder when teletext stream is found
Add timing support for teletext streams
Wrap teletext data in PES headers for decoder compatibility

Known Limitation

WTV files store teletext in Microsoft's VBI sample format, which differs from standard DVB teletext data units. The decoder will process the data but may not extract subtitles from all WTV files. A warning message is displayed when teletext is detected.

Note: Even FFmpeg's libzvbi fails to decode the test sample with "Error decoding subtitles: Invalid data found when processing input", confirming this is a format compatibility issue rather than a CCExtractor bug.

Test Results

With the sample from #1391:

Before: Teletext stream not detected, 0 bytes output
After: Teletext stream detected, 1014 packets processed, warning displayed about format limitation

Fixes #1391

🤖 Generated with Claude Code

_{🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.}

## 📋 Pull Request Information **Original PR:** https://github.com/CCExtractor/ccextractor/pull/1869 **Author:** [@cfsmp3](https://github.com/cfsmp3) **Created:** 12/20/2025 **Status:** ✅ Merged **Merged:** 12/21/2025 **Merged by:** [@cfsmp3](https://github.com/cfsmp3) **Base:** `master` ← **Head:** `fix/wtv-teletext-detection-1391` --- ### 📝 Commits (2) - [`e87807e`](https://github.com/CCExtractor/ccextractor/commit/e87807ec27d2f978c3bfdaa9d63947e1902c00a1) feat(wtv): Add DVB teletext stream detection in WTV files - [`60cec9e`](https://github.com/CCExtractor/ccextractor/commit/60cec9e6deb1a5ec90d3c69e0759c89c7806de5d) style: Fix clang-format indentation ### 📊 Changes **2 files changed** (+102 additions, -4 deletions) <details> <summary>View changed files</summary> 📝 `src/lib_ccx/wtv_constants.h` (+2 -0) 📝 `src/lib_ccx/wtv_functions.c` (+100 -4) </details> ### 📄 Description ## Summary - Adds detection of DVB teletext streams in WTV (Windows TV) files - Previously, teletext streams were silently ignored, producing empty output files ## Changes - Add `WTV_STREAM_TELETEXT` GUID to recognize DVB teletext streams - Detect teletext by examining format subtype GUID at offset 0x4C in MSTVCAPTION metadata - Initialize teletext decoder when teletext stream is found - Add timing support for teletext streams - Wrap teletext data in PES headers for decoder compatibility ## Known Limitation WTV files store teletext in Microsoft's VBI sample format, which differs from standard DVB teletext data units. The decoder will process the data but may not extract subtitles from all WTV files. A warning message is displayed when teletext is detected. Note: Even FFmpeg's libzvbi fails to decode the test sample with "Error decoding subtitles: Invalid data found when processing input", confirming this is a format compatibility issue rather than a CCExtractor bug. ## Test Results With the sample from #1391: - **Before:** Teletext stream not detected, 0 bytes output - **After:** Teletext stream detected, 1014 packets processed, warning displayed about format limitation Fixes #1391 🤖 Generated with [Claude Code](https://claude.com/claude-code) --- <sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>

claunia added the pull-request label 2026-01-29 17:23:15 +00:00

Sign in to join this conversation.

1 Participants

Notifications

Due Date

No due date set.

Dependencies

No dependencies set.

Reference: starred/ccextractor#2643