Modularize ffmepg-core and update tests

wasm/build-scripts/build-ffmpeg.sh

@@ -17,8 +17,10 @@ ARGS=(
   -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 MODULARIZE=1                               # use modularized version to be more flexible
+  -s EXPORT_NAME="createFFmpegCore"             # assign export name for browser
   -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 EXTRA_EXPORTED_RUNTIME_METHODS="[FS, cwrap, ccall, setValue, writeAsciiToMemory]"   # export preamble funcs
   -s INITIAL_MEMORY=1073741824                  # 1073741824 bytes = 1 GB
 )
 emcc "${ARGS[@]}"

wasm/ffmpeg.js

 const path = require('path');
 const fs = require('fs');
-const Module = require('./dist/ffmpeg-core');
+const createFFmpegCore = require('./dist/ffmpeg-core');
 
-Module.onRuntimeInitialized = () => {
-  const filePath = path.join(__dirname, 'tests', 'data', 'video-15s.avi');
+(async () => {
+  let resolve = null;
+  const Core = await createFFmpegCore({
+    printErr: (m) => console.log(m),
+    print: (m) => {
+      console.log(m);
+      if (m.startsWith('FFMPEG_END')) {
+        resolve();
+      }
+    }
+  });
+  const filePath = path.join(__dirname, 'tests', 'data', 'video-3s.avi');
   const data = Uint8Array.from(fs.readFileSync(filePath));
-  Module.FS.writeFile('video.avi', data);
+  Core.FS.writeFile('video.avi', data);
 
-  const ffmpeg = Module.cwrap('proxy_main', 'number', ['number', 'number']);
+  const ffmpeg = Core.cwrap('proxy_main', 'number', ['number', 'number']);
   const args = ['ffmpeg', '-hide_banner', '-report', '-i', 'video.avi', 'video.mp4'];
-  const argsPtr = Module._malloc(args.length * Uint32Array.BYTES_PER_ELEMENT);
+  const argsPtr = Core._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');
+    const buf = Core._malloc(s.length + 1);
+    Core.writeAsciiToMemory(s, buf);
+    Core.setValue(argsPtr + (Uint32Array.BYTES_PER_ELEMENT * idx), buf, 'i32');
   });
   console.time('execution time');
   ffmpeg(args.length, argsPtr);
-
-  /*
-   * The execution of ffmpeg is not synchronized,
-   * so we need to parse the log file to check if completed.
-   */
-  const timer = setInterval(() => {
-    const logFileName = Module.FS.readdir('.').find(name => name.endsWith('.log'));
-    if (typeof logFileName !== 'undefined') {
-      const log = String.fromCharCode.apply(null, Module.FS.readFile(logFileName));
-      if (log.includes("frames successfully decoded")) {
-        clearInterval(timer);
-        const output = Module.FS.readFile('video.mp4');
-        fs.writeFileSync('video.mp4', output);
-        console.timeEnd('execution time');
-        process.exit(1);
-      }
-    }
-  }, 500);
-};
+  await new Promise((_resolve) => { resolve = _resolve });
+  const output = Core.FS.readFile('video.mp4');
+  fs.writeFileSync(path.join(__dirname, 'video.mp4'), output);
+  console.timeEnd('execution time');
+  process.exit(1);
+})();

wasm/tests/bootstrap.test.js

-const {
-  initModule,
-  parseArgs,
-} = require('./utils');
-let Module = null;
-let ffmpeg = null;
-
-beforeAll(async () => {
-  Module = await initModule();
-  ffmpeg = Module.cwrap('proxy_main', 'number', ['number', 'number']);
-});
-
-test('test', () => {
-  const ret = ffmpeg(...parseArgs(['ffmpeg', '-v']));
-  expect(ret).toBe(0);
-});

wasm/tests/transcode.test.js

+const fs = require('fs');
+const path = require('path');
+const createFFmpegCore = require('../dist/ffmpeg-core');
+const { parseArgs, ffmpeg } = require('./utils');
+const filePath = path.join(__dirname, 'data', 'video-3s.avi');
+let Core = null;
+let resolve = null;
+let data = null;
+
+beforeAll(async () => {
+  data = Uint8Array.from(fs.readFileSync(filePath));
+  Core = await createFFmpegCore({
+    printErr: () => {},
+    print: (m) => {
+      if (m.startsWith('FFMPEG_END')) {
+        resolve();
+      }
+    },
+  });
+  Core.FS.writeFile('video.avi', data);
+});
+
+test('transcode avi to x264 mp4', async () => {
+  ffmpeg(Core, ['-i', 'video.avi', 'video.mp4']);
+  await new Promise((_resolve) => { resolve = _resolve });
+  const fileSize = Core.FS.readFile('video.mp4').length;
+  Core.FS.unlink('video.mp4');
+  expect(fileSize).toBe(98326);
+}, 30000);
+
+test('transcode avi to x264 mp4 twice', async () => {
+  for (let i = 0 ; i < 2; i++) {
+    ffmpeg(Core, ['-i', 'video.avi', 'video.mp4']);
+    await new Promise((_resolve) => { resolve = _resolve });
+    const fileSize = Core.FS.readFile('video.mp4').length;
+    Core.FS.unlink('video.mp4');
+    expect(fileSize).toBe(98326);
+  }
+}, 30000);

wasm/tests/utils.js

-let Module = null;
-
-exports.initModule = () => (
-  new Promise((resolve) => {
-    const _Module = require('../dist/ffmpeg-core.js');
-    _Module.onRuntimeInitialized = () => {
-      Module = _Module;
-      resolve(Module);
-    }
-  })
-);
-
-exports.parseArgs = (args) => {
-  const argsPtr = Module._malloc(args.length * Uint32Array.BYTES_PER_ELEMENT);
+const parseArgs = (Core, args) => {
+  const argsPtr = Core._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');
+    const buf = Core._malloc(s.length + 1);
+    Core.writeAsciiToMemory(s, buf);
+    Core.setValue(argsPtr + (Uint32Array.BYTES_PER_ELEMENT * idx), buf, 'i32');
   });
   return [args.length, argsPtr];
 };
+
+const ffmpeg = (Core, args) => {
+  Core.ccall(
+    'proxy_main',
+    'number',
+    ['number', 'number'],
+    parseArgs(Core, ['ffmpeg', '-nostdin', ...args]),
+  );
+}
+
+module.exports = {
+  ffmpeg,
+  parseArgs,
+}