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Fix JavaScript video codec discovery and round trip #5415

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Merged
shai-almog merged 5 commits into from
Jul 19, 2026
Merged

Fix JavaScript video codec discovery and round trip #5415

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def0bb3
Probe JavaScript video encoder capabilities
shai-almog Jul 19, 2026
3809e32
Probe actual WebCodecs encoder output
shai-almog Jul 19, 2026
cd53d48
Reuse JavaScript video encoder capability probes
shai-almog Jul 19, 2026
309d8c0
Match JavaScript video and audio codecs
shai-almog Jul 19, 2026
6403053
Add round-trip test copyright header
shai-almog Jul 19, 2026
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71 changes: 66 additions & 5 deletions Ports/JavaScriptPort/src/main/java/com/codename1/impl/html5/HTML5VideoIO.java
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Original file line number Diff line number Diff line change
Expand Up @@ -49,7 +49,7 @@
/// which lets the browser's asynchronous `seeked`/`loadedmetadata` events fire while a
/// decode call appears synchronous to the caller.
///
/// **Encoding** uses the WebCodecs `VideoEncoder`/`AudioEncoder` (H.264/VP9 + AAC/Opus)
/// **Encoding** uses the WebCodecs `VideoEncoder`/`AudioEncoder` (H.264/VP8/VP9 + AAC/Opus)
/// muxed into MP4/WebM with the standalone `mp4-muxer`/`webm-muxer` libraries (loaded
/// from a CDN, the same mechanism the port uses for VideoJS). Frames are pushed as RGBA,
/// the muxer's in-memory buffer is handed back to Java on `close()` and written to the
Expand All @@ -62,10 +62,19 @@ public VideoCodec[] getAvailableEncoders() {
return new VideoCodec[0];
}
List<VideoCodec> out = new ArrayList<VideoCodec>();
out.add(new VideoCodec(CODEC_H264, "H.264 (WebCodecs)", "video/avc", true, true, false, true, -1, -1, new String[]{CONTAINER_MP4}));
out.add(new VideoCodec(CODEC_VP9, "VP9 (WebCodecs)", "video/vp9", true, true, false, true, -1, -1, new String[]{CONTAINER_WEBM}));
if (cn1AudioWebCodecsAvailable()) {
if (cn1VideoEncoderSupported("avc1.42001f")) {
out.add(new VideoCodec(CODEC_H264, "H.264 (WebCodecs)", "video/avc", true, true, false, true, -1, -1, new String[]{CONTAINER_MP4}));
}
if (cn1VideoEncoderSupported("vp8")) {
out.add(new VideoCodec(CODEC_VP8, "VP8 (WebCodecs)", "video/vp8", true, true, false, true, -1, -1, new String[]{CONTAINER_WEBM}));
}
if (cn1VideoEncoderSupported("vp09.00.10.08")) {
out.add(new VideoCodec(CODEC_VP9, "VP9 (WebCodecs)", "video/vp9", true, true, false, true, -1, -1, new String[]{CONTAINER_WEBM}));
}
if (cn1AudioWebCodecsAvailable() && cn1AudioEncoderSupported("mp4a.40.2")) {
out.add(new VideoCodec(CODEC_AAC, "AAC (WebCodecs)", "audio/mp4a-latm", false, true, false, false, -1, -1, new String[]{CONTAINER_MP4}));
}
if (cn1AudioWebCodecsAvailable() && cn1AudioEncoderSupported("opus")) {
out.add(new VideoCodec(CODEC_OPUS, "Opus (WebCodecs)", "audio/opus", false, true, false, false, -1, -1, new String[]{CONTAINER_WEBM}));
}
return out.toArray(new VideoCodec[out.size()]);
Expand Down Expand Up @@ -211,6 +220,24 @@ static final class Writer extends VideoWriter {
this.hasAudio = cfg.isHasAudio();
this.outPath = cfg.getPath();

boolean webm = CONTAINER_WEBM.equals(cfg.getContainer());
boolean mp4 = CONTAINER_MP4.equals(cfg.getContainer());
if (!webm && !mp4) {
throw new IOException("Unsupported JavaScript video container: " + cfg.getContainer());
}
if (webm && !CODEC_VP8.equals(cfg.getVideoCodec()) && !CODEC_VP9.equals(cfg.getVideoCodec())) {
throw new IOException("WebM requires VP8 or VP9 video, not " + cfg.getVideoCodec());
}
if (mp4 && !CODEC_H264.equals(cfg.getVideoCodec())) {
throw new IOException("MP4 requires H.264 video, not " + cfg.getVideoCodec());
}
if (hasAudio && webm && !CODEC_OPUS.equals(cfg.getAudioCodec())) {
throw new IOException("WebM requires Opus audio, not " + cfg.getAudioCodec());
}
if (hasAudio && mp4 && !CODEC_AAC.equals(cfg.getAudioCodec())) {
throw new IOException("MP4 requires AAC audio, not " + cfg.getAudioCodec());
}

cn1EncEnsureLibs();
long start = System.currentTimeMillis();
while (!cn1EncLibsReady(cfg.getContainer())) {
Expand All @@ -223,8 +250,12 @@ static final class Writer extends VideoWriter {
if (br <= 0) {
br = (int) Math.max(800000L, Math.min((long) (width * (long) height * Math.max(1f, frameRate) * 0.10), 100000000L));
}
int audioBr = cfg.getAudioBitRate();
if (hasAudio && audioBr <= 0) {
audioBr = 128000;
}
this.peer = cn1EncOpen(cfg.getContainer(), cfg.getVideoCodec(), width, height, Math.round(frameRate), br,
hasAudio, cfg.getAudioCodec(), cfg.getAudioBitRate(), cfg.getSampleRate(), cfg.getAudioChannels());
hasAudio, cfg.getAudioCodec(), audioBr, cfg.getSampleRate(), cfg.getAudioChannels());
if (peer == 0) {
throw new IOException("Failed to configure the WebCodecs encoder: " + safeError(0));
}
Expand Down Expand Up @@ -341,6 +372,36 @@ private static String safeError(int peer) {
@JSBody(params = {}, script = "return (typeof AudioEncoder !== 'undefined' && typeof AudioData !== 'undefined');")
private static native boolean cn1AudioWebCodecsAvailable();

@JSBody(params = {"codec"}, script =
"if (typeof VideoEncoder === 'undefined') { return false; }"
+ "var encoder = null;"
+ "try {"
+ " encoder = new VideoEncoder({ output: function() {}, error: function() {} });"
+ " var config = { codec: codec, width: 128, height: 96, bitrate: 800000, framerate: 6 };"
+ " if (codec.indexOf('avc1.') === 0) { config.avc = { format: 'avc' }; }"
+ " encoder.configure(config);"
+ " encoder.close();"
+ " return true;"
+ "} catch (e) {"
+ " try { if (encoder && encoder.state !== 'closed') { encoder.close(); } } catch (ignored) {}"
+ " return false;"
+ "}")
private static native boolean cn1VideoEncoderSupported(String codec);

@JSBody(params = {"codec"}, script =
"if (typeof AudioEncoder === 'undefined') { return false; }"
+ "var encoder = null;"
+ "try {"
+ " encoder = new AudioEncoder({ output: function() {}, error: function() {} });"
+ " encoder.configure({ codec: codec, sampleRate: 48000, numberOfChannels: 1, bitrate: 128000 });"
+ " encoder.close();"
+ " return true;"
+ "} catch (e) {"
+ " try { if (encoder && encoder.state !== 'closed') { encoder.close(); } } catch (ignored) {}"
+ " return false;"
+ "}")
private static native boolean cn1AudioEncoderSupported(String codec);

// ============================================================= JS: decoder

@JSBody(params = {"url"}, script =
Expand Down
18 changes: 18 additions & 0 deletions Ports/JavaScriptPort/src/main/webapp/port.js
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Original file line number Diff line number Diff line change
Expand Up @@ -2328,6 +2328,24 @@ bindNative([
return (yield* cn1VideoIoHost({ op: "audioWebCodecsAvailable" })) ? 1 : 0;
});

bindNative([
"cn1_com_codename1_impl_html5_HTML5VideoIO_cn1VideoEncoderSupported_java_lang_String_R_boolean",
"cn1_com_codename1_impl_html5_HTML5VideoIO_cn1VideoEncoderSupported___java_lang_String_R_boolean"
], function*(codec) {
return (yield* cn1VideoIoHost({
op: "videoEncoderSupported", codec: jvm.toNativeString(codec)
})) ? 1 : 0;
});

bindNative([
"cn1_com_codename1_impl_html5_HTML5VideoIO_cn1AudioEncoderSupported_java_lang_String_R_boolean",
"cn1_com_codename1_impl_html5_HTML5VideoIO_cn1AudioEncoderSupported___java_lang_String_R_boolean"
], function*(codec) {
return (yield* cn1VideoIoHost({
op: "audioEncoderSupported", codec: jvm.toNativeString(codec)
})) ? 1 : 0;
});

bindNative([
"cn1_com_codename1_impl_html5_HTML5VideoIO_cn1VideoOpen_java_lang_String_R_int"
], function*(url) {
Expand Down
84 changes: 63 additions & 21 deletions ...n/src/main/java/com/codenameone/examples/hellocodenameone/tests/VideoIORoundTripTest.java
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Original file line number Diff line number Diff line change
@@ -1,3 +1,25 @@
/*
* Copyright (c) 2026, Codename One and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Codename One designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Codename One through http://www.codenameone.com/ if you
* need additional information or have any questions.
*/
package com.codenameone.examples.hellocodenameone.tests;

import com.codename1.io.FileSystemStorage;
Expand Down Expand Up @@ -78,23 +100,48 @@ private void runRoundTrip() {
return;
}

// Pick an available video codec (prefer H.264) and audio codec (prefer AAC).
String videoCodec = null;
String audioCodec = null;
// Pick a container-compatible pair. Audio and video codecs cannot be
// selected independently: Opus is valid for WebM but not MP4, while
// AAC is valid for MP4 but not WebM. Prefer a complete A/V round trip,
// then fall back to a video-only round trip when the browser has no
// compatible audio encoder.
boolean h264 = false;
boolean vp8 = false;
boolean vp9 = false;
boolean aac = false;
boolean opus = false;
for (VideoCodec c : io.getAvailableEncoders()) {
if (c.isVideo()) {
if (VideoIO.CODEC_H264.equals(c.getId())) {
videoCodec = c.getId();
} else if (videoCodec == null) {
videoCodec = c.getId();
}
} else {
if (VideoIO.CODEC_AAC.equals(c.getId())) {
audioCodec = c.getId();
} else if (audioCodec == null) {
audioCodec = c.getId();
}
}
String id = c.getId();
h264 |= VideoIO.CODEC_H264.equals(id);
vp8 |= VideoIO.CODEC_VP8.equals(id);
vp9 |= VideoIO.CODEC_VP9.equals(id);
aac |= VideoIO.CODEC_AAC.equals(id);
opus |= VideoIO.CODEC_OPUS.equals(id);
}

String videoCodec;
String audioCodec;
if (h264 && aac) {
videoCodec = VideoIO.CODEC_H264;
audioCodec = VideoIO.CODEC_AAC;
} else if (vp8 && opus) {
videoCodec = VideoIO.CODEC_VP8;
audioCodec = VideoIO.CODEC_OPUS;
} else if (vp9 && opus) {
videoCodec = VideoIO.CODEC_VP9;
audioCodec = VideoIO.CODEC_OPUS;
} else if (h264) {
videoCodec = VideoIO.CODEC_H264;
audioCodec = null;
} else if (vp8) {
videoCodec = VideoIO.CODEC_VP8;
audioCodec = null;
} else if (vp9) {
videoCodec = VideoIO.CODEC_VP9;
audioCodec = null;
} else {
videoCodec = null;
audioCodec = null;
}
if (videoCodec == null) {
skip("no-video-encoder-on-" + Display.getInstance().getPlatformName());
Expand All @@ -105,11 +152,6 @@ private void runRoundTrip() {
String container = webm ? VideoIO.CONTAINER_WEBM : VideoIO.CONTAINER_MP4;
String mime = webm ? "video/webm" : "video/mp4";
boolean withAudio = audioCodec != null;
if (webm && withAudio && VideoIO.CODEC_AAC.equals(audioCodec)) {
// AAC isn't a WebM audio codec; only keep audio if Opus is available.
withAudio = io.isEncoderSupported(VideoIO.CODEC_OPUS);
audioCodec = VideoIO.CODEC_OPUS;
}

String path = FileSystemStorage.getInstance().getAppHomePath()
+ "/cn1-videoio-roundtrip-" + System.currentTimeMillis() + (webm ? ".webm" : ".mp4");
Expand Down
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