Add closure flag, documents and update test data

wasm/build-scripts/build-ffmpeg.sh

@@ -11,13 +11,14 @@ ARGS=(
   -Qunused-arguments
   -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 -lpostproc -lm -lx264 -pthread
-  -O3                                           # Optimize code with performance first
+  -O3                                           # optimize code with performance first
+  --closure 1                                   # code size optimization
   -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=268435456                   # 268435456 bytes = 256 MB
+  -s INITIAL_MEMORY=1073741824                  # 1073741824 bytes = 1 GB
 )
 emcc "${ARGS[@]}"

wasm/build-scripts/build-x264.sh

@@ -7,12 +7,12 @@ BUILD_DIR=$2
 
 cd $ROOT
 ARGS=(
-  --prefix=$BUILD_DIR                 # install library in a build directory for FFmpeg to include
-  --host=i686-gnu                     # use i686 linux
-  --enable-static                     # enable building static library
-  --disable-cli                       # disable cli tools
-  --disable-asm                       # disable asm optimization
-  --extra-cflags="-s USE_PTHREADS=1"  # pass this flags for using pthreads
+  --prefix=$BUILD_DIR                                 # install library in a build directory for FFmpeg to include
+  --host=i686-gnu                                     # use i686 linux
+  --enable-static                                     # enable building static library
+  --disable-cli                                       # disable cli tools
+  --disable-asm                                       # disable asm optimization
+  --extra-cflags="-s USE_PTHREADS=1 -O3 --closure 1"  # flags to use pthread and code optimization
 )
 emconfigure ./configure "${ARGS[@]}"
 emmake make install-lib-static -j4

wasm/build-scripts/configure.sh

@@ -3,8 +3,8 @@
 set -eo pipefail
 
 BUILD_DIR=$1
-CFLAGS="-s USE_PTHREADS -O3 -I$BUILD_DIR/include"
-LDFLAGS="$CFLAGS -L$BUILD_DIR/lib -s INITIAL_MEMORY=33554432" # 33554432 bytes = 32 MB
+CFLAGS="-s USE_PTHREADS -I$BUILD_DIR/include -O3 --closure 1"
+LDFLAGS="$CFLAGS -L$BUILD_DIR/lib"
 ARGS=(
   --target-os=none        # use none to prevent any os specific configurations
   --arch=x86_32           # use x86_32 to achieve minimal architectural optimization
@@ -16,6 +16,7 @@ ARGS=(
   --disable-doc           # disable doc
   --enable-gpl            # required by x264
   --enable-libx264        # enable x264
+  --disable-debug         # disable debug info, required by closure
   --extra-cflags="$CFLAGS"
   --extra-cxxflags="$CFLAGS"
   --extra-ldflags="$LDFLAGS"

wasm/docs/optimization-flags.md

+# Optimization Flags
+
+Statistics of using different flags to optimize code:
+
+| flags | build time | execution time | ffmpeg-core.js size | ffmpeg-core.wasm size | ffmpeg.worker.js size |
+| ----- | ---------- | ---------------| ------------------- | --------------------- | --------------------- |
+| N/A                   | 6m 19s  | 7.5s | 584,269 bytes | 30,406,730 bytes | 9,048 bytes |
+| -Oz                   | 7m 40s  | 6s   | 295,674 bytes | 14,919,062 bytes | 3,363 bytes |
+| -O3                   | 8m 36s  | 5s   | 295,676 bytes | 17,746,341 bytes | 3,363 bytes |
+| -O3 --closure 1       | 10m 20s | 5s   | 142,076 bytes | 17,746,766 bytes | 3,624 bytes |
+| -O3 --closure 1 -flto | 12m 36s | 5s   | 141,516 bytes | 18,960,830 bytes | 3,624 bytes |
+
+The best one to use in case of performance is `-O3 --closure 1`.

wasm/ffmpeg.js

+const path = require('path');
 const fs = require('fs');
 const Module = require('./dist/ffmpeg-core');
 
 Module.onRuntimeInitialized = () => {
-  const data = Uint8Array.from(fs.readFileSync('tests/data/flame.avi'));
-  Module.FS.writeFile('flame.avi', data);
+  const filePath = path.join(__dirname, 'tests', 'data', 'video-15s.avi');
+  const data = Uint8Array.from(fs.readFileSync(filePath));
+  Module.FS.writeFile('video.avi', data);
 
   const ffmpeg = Module.cwrap('proxy_main', 'number', ['number', 'number']);
-  const args = ['ffmpeg', '-hide_banner', '-report', '-i', 'flame.avi', 'flame.mp4'];
+  const args = ['ffmpeg', '-hide_banner', '-report', '-i', 'video.avi', 'video.mp4'];
   const argsPtr = Module._malloc(args.length * Uint32Array.BYTES_PER_ELEMENT);
   args.forEach((s, idx) => {
     const buf = Module._malloc(s.length + 1);
@@ -26,8 +28,8 @@ Module.onRuntimeInitialized = () => {
       const log = String.fromCharCode.apply(null, Module.FS.readFile(logFileName));
       if (log.includes("frames successfully decoded")) {
         clearInterval(timer);
-        const output = Module.FS.readFile('flame.mp4');
-        fs.writeFileSync('flame.mp4', output);
+        const output = Module.FS.readFile('video.mp4');
+        fs.writeFileSync('video.mp4', output);
         console.timeEnd('execution time');
         process.exit(1);
       }

data @ e5e81752

-Subproject commit de37794135511be2806ff02bd4dea28adbbf27db
+Subproject commit e5e817520bcba4b56b394989ba3d136d9f110b1c