Merge branch 'master' into null-terminated-frames

Author: pszemus

.github/PULL_REQUEST_TEMPLATE.md

@@ -2,19 +2,26 @@
 
 **In raising this pull request, I confirm the following (please check boxes):**
 
+Reason for this PR:
+
+- [ ] This PR adds new functionality.
+- [ ] This PR fixes a bug that I have personally experienced or that a real user has reported and for which a sample exists.
+- [ ] This PR is porting code from C to Rust.
+
+Sanity check:
 - [ ] I have read and understood the [contributors guide](https://github.com/CCExtractor/ccextractor/blob/master/.github/CONTRIBUTING.md).
 - [ ] I have checked that another pull request for this purpose does not exist.
-- [ ] I have considered, and confirmed that this submission will be valuable to others.
-- [ ] I accept that this submission may not be used, and the pull request closed at the will of the maintainer.
-- [ ] I give this submission freely, and claim no ownership to its content.
-- [ ] **I have mentioned this change in the [changelog](https://github.com/CCExtractor/ccextractor/blob/master/docs/CHANGES.TXT).**
+- [ ] If the PR adds new functionality, I've added it to the changelog. If it's just a bug fix, I have NOT added it to the changelog.
+- [ ] I am NOT adding new C code unless it's to fix an existing, reproducible bug.
+
+Repro instructions:
+
+This is *essential*. We will not merge ANY PR that doesn't come with detailed instructions, *including a sample*. We don't want
+"fixes" for theoretical issues that an AI agent found, without context. If you can't reproduce the bug, don't send a PR. 
 
-**My familiarity with the project is as follows (check one):**
+Creating PRs with AI is very quick, but we still have humans (even if AI assisted) going over each.
 
-- [ ] I have never used CCExtractor.
-- [ ] I have used CCExtractor just a couple of times.
-- [ ] I absolutely love CCExtractor, but have not contributed previously.
-- [ ] I am an active contributor to CCExtractor.
+Be mindful of reviewers' time.
 
 ---
 

.github/workflows/build_linux.yml

@@ -33,7 +33,7 @@ jobs:
       run: sudo apt update && sudo apt-get install libgpac-dev libtesseract-dev libavcodec-dev libavdevice-dev libx11-dev libxcb1-dev libxcb-shm0-dev
     - uses: actions/checkout@v6
     - name: build
-      run: ./build -hardsubx
+      run: ./build -hardsubx -min-rust
       working-directory: ./linux
     - name: Display version information
       run: ./ccextractor --version
@@ -49,6 +49,29 @@ jobs:
       with:
         name: CCExtractor Linux build
         path: ./linux/artifacts
+  build_shell_migrations:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Install dependencies
+      run: sudo apt update && sudo apt-get install libgpac-dev libtesseract-dev libavcodec-dev libavdevice-dev libx11-dev libxcb1-dev libxcb-shm0-dev
+    - uses: actions/checkout@v6
+    - name: build
+      run: ./build -hardsubx
+      working-directory: ./linux
+    - name: Display version information
+      run: ./ccextractor --version
+      working-directory: ./linux
+    - name: Prepare artifacts
+      run: mkdir ./linux/artifacts
+    - name: Copy release artifact
+      run: cp ./linux/ccextractor ./linux/artifacts/
+    # NOTE: The sample-platform test runner (CCExtractor/sample-platform)
+    # matches artifact names exactly. Update Artifact_names in
+    # mod_ci/controllers.py there if you rename this artifact.
+    - uses: actions/upload-artifact@v7
+      with:
+        name: CCExtractor Linux build (with migrations)
+        path: ./linux/artifacts
   build_autoconf:
     runs-on: ubuntu-latest
     steps:

.github/workflows/build_windows.yml

@@ -113,15 +113,15 @@ jobs:
         with:
           arch: ${{ matrix.arch }}
 
-      # Build Release-Full
-      - name: Build Release-Full
+      # Build Release-Full (min Rust — C paths where available)
+      - name: Build Release-Full (min Rust)
         env:
           LIBCLANG_PATH: "C:\\Program Files\\LLVM\\lib"
           LLVM_CONFIG_PATH: "C:\\Program Files\\LLVM\\bin\\llvm-config"
           BINDGEN_EXTRA_CLANG_ARGS: -fmsc-version=0
           VCPKG_ROOT: ${{ github.workspace }}/vcpkg
           VCPKG_DEFAULT_TRIPLET: ${{ matrix.vcpkg_triplet }}
-        run: msbuild ccextractor.sln /p:Configuration=Release-Full /p:Platform=${{ matrix.platform }} /p:GpacDir="${{ matrix.gpac_install }}"
+        run: msbuild ccextractor.sln /p:Configuration=Release-Full /p:Platform=${{ matrix.platform }} /p:GpacDir="${{ matrix.gpac_install }}" /p:ExtraDefines=DISABLE_RUST
         working-directory: ./windows
 
       - name: Display Release version information
@@ -140,6 +140,25 @@ jobs:
             ./windows/${{ matrix.outdir }}Release-Full/ccextractorwinfull.exe
             ./windows/${{ matrix.outdir }}Release-Full/*.dll
 
+      # Build Release-Full (with migrations — max Rust)
+      - name: Build Release-Full (with migrations)
+        env:
+          LIBCLANG_PATH: "C:\\Program Files\\LLVM\\lib"
+          LLVM_CONFIG_PATH: "C:\\Program Files\\LLVM\\bin\\llvm-config"
+          BINDGEN_EXTRA_CLANG_ARGS: -fmsc-version=0
+          VCPKG_ROOT: ${{ github.workspace }}/vcpkg
+          VCPKG_DEFAULT_TRIPLET: ${{ matrix.vcpkg_triplet }}
+        run: msbuild ccextractor.sln /t:Rebuild /p:Configuration=Release-Full /p:Platform=${{ matrix.platform }} /p:GpacDir="${{ matrix.gpac_install }}"
+        working-directory: ./windows
+
+      - name: Upload Release artifact (with migrations)
+        uses: actions/upload-artifact@v7
+        with:
+          name: CCExtractor Windows ${{ matrix.arch }} Release build (with migrations)
+          path: |
+            ./windows/${{ matrix.outdir }}Release-Full/ccextractorwinfull.exe
+            ./windows/${{ matrix.outdir }}Release-Full/*.dll
+
       # Build Debug-Full (reuses cached Cargo artifacts)
       - name: Build Debug-Full
         env:

docs/CHANGES.TXT

@@ -1,8 +1,11 @@
 0.96.7 (unreleased)
 -------------------
 - New: Allow output \0 terminated frames via --null-terminated
+- New: Added ASS/SSA \pos-based positioning for CEA-608 captions when layout is simple (1–2 rows) (#1726)
 - Fix: Remove strdup() memory leaks in WebVTT styling encoder, fix invalid CSS rgba(0,256,0) green value, fix missing free(unescaped) on write-error path (#2154)
 - Fix: Prevent crash in Rust timing module when logging out-of-range PTS/FTS timestamps from malformed streams.
+- Fix: Resolve Windows MSVC debug build crash caused by cross-CRT invalid free on Rust-allocated output_filename (#2126)
+- Fix: Use dynamic current_fps instead of hardcoded 29.97 in CEA-708 SCC frame delay calculations (#2172)
 
 0.96.6 (2026-02-19)
 -------------------

linux/build

@@ -24,6 +24,11 @@ while [[ $# -gt 0 ]]; do
       BLD_LINKER="$BLD_LINKER -lswscale -lavutil -pthread -lavformat -lavcodec -lavfilter -lxcb-shm -lxcb -lX11 -llzma -lswresample"
       shift
       ;;
+    -min-rust)
+      MIN_RUST=true
+      BLD_FLAGS="$BLD_FLAGS -DDISABLE_RUST"
+      shift
+      ;;
     -system-libs)
       USE_SYSTEM_LIBS=true
       shift

src/CMakeLists.txt

@@ -6,6 +6,7 @@ include (CTest)
 option (WITH_FFMPEG "Build using FFmpeg demuxer and decoder" OFF)
 option (WITH_OCR "Build with OCR (Optical Character Recognition) feature" OFF)
 option (WITH_HARDSUBX "Build with support for burned-in subtitles" OFF)
+option (VBI_DEBUG "Enable VBI decoder debug output" OFF)
 
 # Version number
 set (CCEXTRACTOR_VERSION_MAJOR 0)
@@ -145,6 +146,11 @@ else (MSVC)
 endif(MSVC)
 
 set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -D_FILE_OFFSET_BITS=64")
+
+if (VBI_DEBUG)
+  add_definitions(-DVBI_DEBUG)
+  message(STATUS "VBI debug output enabled")
+endif (VBI_DEBUG)
 add_subdirectory (lib_ccx)
 
 aux_source_directory(${PROJECT_SOURCE_DIR} SOURCEFILE)
@@ -202,7 +208,9 @@ if (PKG_CONFIG_FOUND AND WITH_OCR)
   pkg_check_modules (LEPTONICA REQUIRED lept)
 
   set (EXTRA_LIBS ${EXTRA_LIBS} ${TESSERACT_LIBRARIES})
+  link_directories(${TESSERACT_LIBRARY_DIRS})
   set (EXTRA_LIBS ${EXTRA_LIBS} ${LEPTONICA_LIBRARIES})
+  link_directories(${LEPTONICA_LIBRARY_DIRS})
 
   set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DENABLE_OCR")
 endif (PKG_CONFIG_FOUND AND WITH_OCR)
@@ -237,7 +245,9 @@ if (PKG_CONFIG_FOUND AND WITH_HARDSUBX)
   pkg_check_modules (LEPTONICA REQUIRED lept)
 
   set (EXTRA_LIBS ${EXTRA_LIBS} ${TESSERACT_LIBRARIES})
+  link_directories(${TESSERACT_LIBRARY_DIRS})
   set (EXTRA_LIBS ${EXTRA_LIBS} ${LEPTONICA_LIBRARIES})
+  link_directories(${LEPTONICA_LIBRARY_DIRS})
 
   set (EXTRA_INCLUDES ${EXTRA_INCLUDES} ${TESSERACT_INCLUDE_DIRS})
   set (EXTRA_INCLUDES ${EXTRA_INCLUDES} ${LEPTONICA_INCLUDE_DIRS})

src/lib_ccx/ccx_decoders_708_output.c

@@ -550,11 +550,11 @@ void dtvcc_write_scc(dtvcc_writer_ctx *writer, dtvcc_service_decoder *decoder, s
 	if (tv->old_cc_time_end > time_show.time_in_ms)
 	{
 		// Correct the frame delay
-		time_show.time_in_ms -= 1000 / 29.97;
+		time_show.time_in_ms -= 1000 / current_fps;
 		print_scc_time(time_show, buf);
 		buf_len = strlen(buf);
 		SCC_SNPRINTF("\t942c 942c");
-		time_show.time_in_ms += 1000 / 29.97;
+		time_show.time_in_ms += 1000 / current_fps;
 		// Clear the buffer and start pop on caption
 		SCC_SNPRINTF("94ae 94ae 9420 9420");
 	}
@@ -566,20 +566,20 @@ void dtvcc_write_scc(dtvcc_writer_ctx *writer, dtvcc_service_decoder *decoder, s
 		buf_len = strlen(buf);
 		SCC_SNPRINTF("\t942c 942c \n\n");
 		// Correct the frame delay
-		time_show.time_in_ms -= 1000 / 29.97;
+		time_show.time_in_ms -= 1000 / current_fps;
 		// Clear the buffer and start pop on caption in new time
 		print_scc_time(time_show, buf + buf_len);
 		buf_len = strlen(buf);
 		SCC_SNPRINTF("\t94ae 94ae 9420 9420");
-		time_show.time_in_ms += 1000 / 29.97;
+		time_show.time_in_ms += 1000 / current_fps;
 	}
 	else
 	{
-		time_show.time_in_ms -= 1000 / 29.97;
+		time_show.time_in_ms -= 1000 / current_fps;
 		print_scc_time(time_show, buf);
 		buf_len = strlen(buf);
 		SCC_SNPRINTF("\t942c 942c 94ae 94ae 9420 9420");
-		time_show.time_in_ms += 1000 / 29.97;
+		time_show.time_in_ms += 1000 / current_fps;
 	}
 
 	int total_subtitle_count = count_captions_lines_scc(tv);

src/lib_ccx/ccx_decoders_vbi.h

@@ -2,7 +2,6 @@
 #define CCX_DECODER_VBI
 
 #include "zvbi/zvbi_decoder.h"
-#define VBI_DEBUG
 
 #include "ccx_decoders_structs.h"
 #include "ccx_decoders_common.h"
@@ -11,6 +10,8 @@ struct ccx_decoder_vbi_cfg
 {
 #ifdef VBI_DEBUG
 	char *debug_file_name;
+#else
+	int reserved; /* ensure non-empty struct in non-debug builds (MSVC C2016) */
 #endif
 };
 
@@ -24,4 +25,4 @@ struct ccx_decoder_vbi_ctx
 #endif
 };
 
-#endif
+#endif

src/lib_ccx/ccx_demuxer.c

@@ -136,7 +136,19 @@ static int ccx_demuxer_open(struct ccx_demuxer *ctx, const char *file)
 
 	if (ctx->auto_stream == CCX_SM_AUTODETECT)
 	{
+		// Temporarily disable binary_concat during stream detection.
+		// detect_stream_type reads up to 1MB (STARTBYTESLENGTH) via
+		// buffered_read_opt. For files smaller than 1MB, hitting EOF
+		// causes buffered_read_opt to call switch_to_next_file (when
+		// binary_concat is enabled), which increments current_file
+		// past the valid range and closes the file descriptor.
+		// This leaves current_file pointing beyond inputfile[], causing
+		// format-specific handlers (e.g. matroska_loop) to crash when
+		// they access inputfile[current_file].
+		int saved_binary_concat = ccx_options.binary_concat;
+		ccx_options.binary_concat = 0;
 		detect_stream_type(ctx);
+		ccx_options.binary_concat = saved_binary_concat;
 		switch (ctx->stream_mode)
 		{
 			case CCX_SM_ELEMENTARY_OR_NOT_FOUND:

src/lib_ccx/ccx_encoders_common.c

@@ -48,6 +48,8 @@ static const char *ssa_header =
     "[Script Info]\n\
 Title: Default file\n\
 ScriptType: v4.00+\n\
+PlayResX: 384\n\
+PlayResY: 288\n\
 \n\
 [V4+ Styles]\n\
 Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding\n\