build: drop FFmpeg from the build and packages

.github/script/check_no_copyleft_libs.sh

@@ -0,0 +1,44 @@
+#!/usr/bin/env bash
+# Fail if a Linux package ships, links or depends on a library FLM dropped for
+# licensing reasons: FFmpeg and the GPL codecs distro FFmpeg pulls in (x264,
+# x265, xvid, libdvdnav/libdvdread), FFTW and GNU readline.
+#
+# Usage: check_no_copyleft_libs.sh <package.tar.gz | package.deb>...
+set -euo pipefail
+
+# Shared-library file names (bundled files and ELF NEEDED entries).
+lib_re='^lib(av(codec|format|util|filter|device)|sw(scale|resample)|postproc|x264|x265|xvidcore|dvdnav|dvdread|fftw3[a-z_]*|readline)[.]so'
+# Debian binary package names (.deb Depends).
+pkg_re='^(libav(codec|format|util|filter|device)|libsw(scale|resample)|libpostproc|libx26[45]|libxvidcore|libdvd(nav|read)|libfftw3|libreadline)'
+
+status=0
+for pkg in "$@"; do
+    tmp=$(mktemp -d)
+    case "$pkg" in
+        *.deb)
+            if dpkg-deb -f "$pkg" Depends | tr ',|' '\n\n' | sed 's/^ *//' | grep -E "$pkg_re"; then
+                echo "::error::$pkg depends on a package listed above"
+                status=1
+            fi
+            dpkg-deb -x "$pkg" "$tmp" ;;
+        *.tar.gz)
+            tar xzf "$pkg" -C "$tmp" ;;
+        *)
+            echo "::error::unknown package type: $pkg"
+            exit 2 ;;
+    esac
+
+    if find "$tmp" \( -type f -o -type l \) -printf '%f\n' | grep -E "$lib_re"; then
+        echo "::error::$pkg bundles a library listed above"
+        status=1
+    fi
+    while IFS= read -r -d '' f; do
+        if readelf -d "$f" 2>/dev/null | sed -n 's/.*(NEEDED).*\[\(.*\)\]/\1/p' | grep -E "$lib_re"; then
+            echo "::error::${f#"$tmp"/} in $pkg links a library listed above"
+            status=1
+        fi
+    done < <(find "$tmp" -type f -print0)
+    rm -rf "$tmp"
+    [ "$status" -eq 0 ] && echo "$pkg: no FFmpeg, GPL codec, FFTW or readline libraries"
+done
+exit "$status"

.github/workflows/asr-test.yml

@@ -16,13 +16,12 @@ name: ASR Test
 # platform) and the same 5 points per set.
 #
 # The trigger paths are the Whisper engine, its NPU kernels and prebuilt NPU
-# libraries, the FFmpeg, audio front end and FFT code, the audio front ends of
+# libraries, the audio decoders, front end and FFT code, the audio front ends of
 # the chat models that transcribe, and the server files that host
 # /v1/audio/transcriptions. Those server files also hold every other endpoint,
 # so any change to them runs this test too. The pull_request and push path
-# lists must stay identical. Shared files such as src/CMakeLists.txt (the Linux
-# FFmpeg version) and lm_config.hpp are left out, since every change touches
-# them.
+# lists must stay identical. Shared files such as src/CMakeLists.txt and
+# lm_config.hpp are left out, since every change touches them.
 #
 # The weekly run catches what no commit changes: Whisper weights republished
 # on Hugging Face, and NPU driver or firmware updates on the runners.
@@ -45,11 +44,9 @@ on:
       - 'src/include/audio/**'
       - 'src/common/AutoModel/*_audio.cpp'
       - 'src/detail/gemma4e_npu/gemma4e_audio*'
-      - 'src/include/fftw3.h'
       - 'src/include/pocketfft/**'
-      - 'src/lib/libfftw3*'
-      - 'src/lib/av*'
-      - 'src/lib/sw*'
+      - 'src/include/dr_libs/**'
+      - 'src/cmake/FlmAudioCodecs.cmake'
       - 'src/server/rest_handler.cpp'
       - 'src/server/server.cpp'
       - 'src/server/multipart.cpp'
@@ -74,11 +71,9 @@ on:
       - 'src/include/audio/**'
       - 'src/common/AutoModel/*_audio.cpp'
       - 'src/detail/gemma4e_npu/gemma4e_audio*'
-      - 'src/include/fftw3.h'
       - 'src/include/pocketfft/**'
-      - 'src/lib/libfftw3*'
-      - 'src/lib/av*'
-      - 'src/lib/sw*'
+      - 'src/include/dr_libs/**'
+      - 'src/cmake/FlmAudioCodecs.cmake'
       - 'src/server/rest_handler.cpp'
       - 'src/server/server.cpp'
       - 'src/server/multipart.cpp'

.github/workflows/debian-portable.yml

@@ -91,6 +91,8 @@ jobs:
         echo "Created tarball with symlinks preserved"
         # The default backend is XRT, so confirm libxrt is bundled.
         tar tzf $GITHUB_WORKSPACE/fastflowlm_${VERSION}_linux.tar.gz | grep libxrt
+        $GITHUB_WORKSPACE/.github/script/check_no_copyleft_libs.sh \
+          $GITHUB_WORKSPACE/fastflowlm_${VERSION}_linux.tar.gz
 
     - name: Upload portable build artifact
       uses: actions/upload-artifact@v4
@@ -140,6 +142,8 @@ jobs:
           LICENSE_RUNTIME.txt \
           LICENSE_BINARY.txt \
           THIRD_PARTY_NOTICES.txt
+        "$GITHUB_WORKSPACE/.github/script/check_no_copyleft_libs.sh" \
+          "$GITHUB_WORKSPACE/models-from-source_fastflowlm_${VERSION}_linux.tar.gz"
 
     - name: Upload models-from-source build artifact
       uses: actions/upload-artifact@v4
@@ -149,28 +153,6 @@ jobs:
         retention-days: 7
         if-no-files-found: error
 
-    - name: Collect FFmpeg logs
-      if: always()
-      shell: bash
-      run: |
-        set -euxo pipefail
-        OUT="${RUNNER_TEMP}/ffmpeg-logs"
-        mkdir -p "${OUT}"
-        find "${GITHUB_WORKSPACE}" -type f \
-          \( -name "configure.log" -o -name "build.log" -o -name "config.log" \) \
-          -path "*/ffmpeg-build/*" \
-          -print \
-          -exec cp --parents {} "${OUT}" \; || true
-
-    - name: Upload FFmpeg logs artifact
-      if: always()
-      uses: actions/upload-artifact@v4
-      with:
-        name: ffmpeg-logs-${{ github.job }}-run${{ github.run_number }}-attempt${{ github.run_attempt }}
-        path: ${{ runner.temp }}/ffmpeg-logs
-        if-no-files-found: warn
-        retention-days: 14
-
   build-HRX-portable:
     runs-on: ubuntu-latest
     strategy:
@@ -254,18 +236,8 @@ jobs:
         echo "Created tarball with symlinks preserved"
         # This build selects the HRX backend, so confirm libhrx is bundled.
         tar tzf $GITHUB_WORKSPACE/HRX_fastflowlm_${VERSION}_linux.tar.gz | grep libhrx
-        # FFmpeg is linked statically from an LGPL source build, so neither flm
-        # nor the tarball may carry a shared FFmpeg (distro builds are GPL) or
-        # the GPL codecs it would drag in.
-        if readelf -d flm-real | grep -E 'NEEDED.*lib(av|sw|postproc)'; then
-          echo "::error::flm-real links a shared FFmpeg library"
-          exit 1
-        fi
-        if tar tzf $GITHUB_WORKSPACE/HRX_fastflowlm_${VERSION}_linux.tar.gz \
-            | grep -E 'lib/lib(av(codec|format|util|filter|device)|sw(scale|resample)|postproc|x264|x265|xvidcore)[.]so'; then
-          echo "::error::tarball bundles a shared FFmpeg or GPL codec library"
-          exit 1
-        fi
+        $GITHUB_WORKSPACE/.github/script/check_no_copyleft_libs.sh \
+          $GITHUB_WORKSPACE/HRX_fastflowlm_${VERSION}_linux.tar.gz
 
     - name: Upload portable build artifact
       uses: actions/upload-artifact@v4
@@ -275,28 +247,6 @@ jobs:
         retention-days: 7
         if-no-files-found: error
 
-    - name: Collect FFmpeg logs
-      if: always()
-      shell: bash
-      run: |
-        set -euxo pipefail
-        OUT="${RUNNER_TEMP}/ffmpeg-logs"
-        mkdir -p "${OUT}"
-        find "${GITHUB_WORKSPACE}" -type f \
-          \( -name "configure.log" -o -name "build.log" -o -name "config.log" \) \
-          -path "*/ffmpeg-build/*" \
-          -print \
-          -exec cp --parents {} "${OUT}" \; || true
-
-    - name: Upload FFmpeg logs artifact
-      if: always()
-      uses: actions/upload-artifact@v4
-      with:
-        name: ffmpeg-logs-${{ github.job }}-run${{ github.run_number }}-attempt${{ github.run_attempt }}
-        path: ${{ runner.temp }}/ffmpeg-logs
-        if-no-files-found: warn
-        retention-days: 14
-
   test-summary:
     runs-on: ubuntu-latest
     needs: build-portable
@@ -307,11 +257,10 @@ jobs:
           echo "# Portable Build Test Results" >> $GITHUB_STEP_SUMMARY
           echo "" >> $GITHUB_STEP_SUMMARY
           echo "✅ FLM built successfully with portable distribution" >> $GITHUB_STEP_SUMMARY
-          echo "✅ FFmpeg statically linked (no external FFmpeg dependencies)" >> $GITHUB_STEP_SUMMARY
+          echo "✅ No FFmpeg, GPL codec, FFTW or readline libraries shipped or linked" >> $GITHUB_STEP_SUMMARY
           echo "✅ XRT and XDNA plugin bundled with distribution" >> $GITHUB_STEP_SUMMARY
           echo "" >> $GITHUB_STEP_SUMMARY
           echo "## Build Configuration" >> $GITHUB_STEP_SUMMARY
-          echo "- **FFmpeg**: Statically linked (built from source)" >> $GITHUB_STEP_SUMMARY
           echo "- **XRT**: Dynamically linked, bundled in lib/" >> $GITHUB_STEP_SUMMARY
           echo "- **XDNA plugin**: Bundled in lib/" >> $GITHUB_STEP_SUMMARY
           echo "" >> $GITHUB_STEP_SUMMARY

.github/workflows/ubuntu-build.yml

@@ -95,6 +95,8 @@ jobs:
           dpkg-buildpackage -b -us -uc
           mv ../fastflowlm_${DEB_VERSION}_amd64.deb ./fastflowlm_${DEB_VERSION}_${{ matrix.distro }}${{ matrix.version }}_amd64.deb
           ls -lah ./fastflowlm_${DEB_VERSION}_${{ matrix.distro }}${{ matrix.version }}_amd64.deb
+          .github/script/check_no_copyleft_libs.sh \
+            ./fastflowlm_${DEB_VERSION}_${{ matrix.distro }}${{ matrix.version }}_amd64.deb
 
       - name: Upload Debian package artifact
         uses: actions/upload-artifact@v4

Dockerfile

@@ -31,16 +31,11 @@ RUN apt update && apt install -y \
     dpkg-dev \
     fakeroot \
     git \
-    libavcodec-dev \
-    libavformat-dev \
-    libavutil-dev \
     libboost-dev \
     libboost-program-options-dev \
     libcurl4-openssl-dev \
     libdrm-dev \
     libedit-dev \
-    libswresample-dev \
-    libswscale-dev \
     libxrt-dev \
     nasm \
     ninja-build \