Update build scripts and add ffmpeg.js

Author: jeromewu

.github/workflows/main.yml

@@ -1,4 +1,4 @@
-name: Pt.3 FFmpeg with x264
+name: Pt.3 FFmpeg v0.1
 # Controls when the action will run. Triggers the workflow on push or pull request
 # events but only for the master branch
 on:
@@ -22,7 +22,7 @@ jobs:
           bash build-with-docker.sh
       - uses: actions/upload-artifact@master
         with:
-          name: ffmpeg-linux
+          name: ffmpeg-core-linux
           path: wasm/dist
   macos-build:
     runs-on: macos-latest
@@ -45,7 +45,7 @@ jobs:
           bash build.sh
       - uses: actions/upload-artifact@master
         with:
-          name: ffmpeg-macos
+          name: ffmpeg-core-macos
           path: wasm/dist
   # Not working with error messsage:
   #   C:\ProgramData\Chocolatey\lib\mingw\tools\install\mingw64\x86_64-w64-mingw32\bin\ar.exe: libavfilter/vsink_null: No such file or directory

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "testdata"]
+	path = testdata
+	url = https://github.com/ffmpegwasm/testdata.git

testdata

@@ -0,0 +1 @@
+*.mp4

wasm/.gitignore

@@ -7,10 +7,15 @@ ARGS=(
   -I. -I./fftools
   -Llibavcodec -Llibavdevice -Llibavfilter -Llibavformat -Llibavresample -Llibavutil -Llibpostproc -Llibswscale -Llibswresample
   -Qunused-arguments
-  -o wasm/dist/ffmpeg.js fftools/ffmpeg_opt.c fftools/ffmpeg_filter.c fftools/ffmpeg_hw.c fftools/cmdutils.c fftools/ffmpeg.c
+  -o wasm/dist/ffmpeg-core.js fftools/ffmpeg_opt.c fftools/ffmpeg_filter.c fftools/ffmpeg_hw.c fftools/cmdutils.c fftools/ffmpeg.c
   -lavdevice -lavfilter -lavformat -lavcodec -lswresample -lswscale -lavutil -lm
-  -s USE_SDL=2                    # use SDL2
-  -s USE_PTHREADS=1               # enable pthreads support
-  -s INITIAL_MEMORY=33554432      # 33554432 bytes = 32 MB
+  -O3                                           # Optimize code with performance first
+  -s USE_SDL=2                                  # use SDL2
+  -s USE_PTHREADS=1                             # enable pthreads support
+  -s PROXY_TO_PTHREAD=1                         # detach main() from browser/UI main thread
+  -s INVOKE_RUN=0                               # not to run the main() in the beginning
+  -s EXPORTED_FUNCTIONS="[_main, _proxy_main]"  # export main and proxy_main funcs
+  -s EXTRA_EXPORTED_RUNTIME_METHODS="[FS, cwrap, setValue, writeAsciiToMemory]"   # export preamble funcs
+  -s INITIAL_MEMORY=33554432                    # 33554432 bytes = 32 MB
 )
 emcc "${ARGS[@]}"

wasm/build-scripts/build-ffmpeg.sh

@@ -2,7 +2,7 @@
 
 set -eo pipefail
 
-CFLAGS="-s USE_PTHREADS"
+CFLAGS="-s USE_PTHREADS -O3"
 LDFLAGS="$CFLAGS -s INITIAL_MEMORY=33554432" # 33554432 bytes = 32 MB
 ARGS=(
   --target-os=none        # use none to prevent any os specific configurations

wasm/build-scripts/configure.sh

@@ -0,0 +1,29 @@
+const fs = require('fs');
+const Module = require('./dist/ffmpeg-core');
+
+Module.onRuntimeInitialized = () => {
+  const data = Uint8Array.from(fs.readFileSync('../testdata/flame.avi'));
+  Module.FS.writeFile('flame.avi', data);
+
+  const ffmpeg = Module.cwrap('proxy_main', 'number', ['number', 'number']);
+  const args = ['ffmpeg', '-hide_banner', '-i', 'flame.avi', 'flame.mp4'];
+  const argsPtr = Module._malloc(args.length * Uint32Array.BYTES_PER_ELEMENT);
+  args.forEach((s, idx) => {
+    const buf = Module._malloc(s.length + 1);
+    Module.writeAsciiToMemory(s, buf);
+    Module.setValue(argsPtr + (Uint32Array.BYTES_PER_ELEMENT * idx), buf, 'i32');
+  });
+  ffmpeg(args.length, argsPtr);
+
+  /*
+   * The execution of ffmpeg is not synchronized,
+   * so we need to set a timer to wait for it completes.
+   */
+  const timer = setInterval(() => {
+    if (Module.FS.readdir('.').find(f => f === 'flame.mp4') !== -1) {
+      clearInterval(timer);
+      const output = Module.FS.readFile('flame.mp4');
+      fs.writeFileSync('flame.mp4', output);
+    }
+  }, 500);
+};