improve bt2020 handling

src/main/ffmpeg.ts

@@ -550,7 +550,29 @@ export function createMediaSourceProcess({ path, videoStreamIndex, audioStreamIn
     if (videoStreamIndex != null) {
       const videoFilters: string[] = [];
       if (fps != null) videoFilters.push(`fps=${fps}`);
-      if (size != null) videoFilters.push(`scale=${size}:${size}:flags=lanczos:force_original_aspect_ratio=decrease:force_divisible_by=2`);
+      const scaleFilterOptions: string[] = [];
+      if (size != null) scaleFilterOptions.push(`${size}:${size}:flags=lanczos:force_original_aspect_ratio=decrease:force_divisible_by=2`);
+
+      // we need to reduce the color space to bt709 for compatibility with most OS'es and hardware combinations
+      // especially because of this bug https://github.com/electron/electron/issues/47947
+      // see also https://www.reddit.com/r/ffmpeg/comments/jlk2zn/how_to_encode_using_bt709/
+      scaleFilterOptions.push('in_color_matrix=auto:in_range=auto:out_color_matrix=bt709:out_range=tv');
+      if (scaleFilterOptions.length > 0) videoFilters.push(`scale=${scaleFilterOptions.join(':')}`);
+
+      // alternatively we could have used `tonemap=hable` instead, but it's slower because it's an additional separate filter.
+      // videoFilters.push('tonemap=hable');
+      // the best would be to use zscale, but it's not yet available in our ffmpeg build, and I think it's slower.
+      // https://gist.github.com/goyuix/033d35846b05733d77f568b754e7c3ea
+      // https://superuser.com/questions/1732301/convert-10bit-hdr-video-to-8bit-frames/1732684#1732684
+
+      videoFilters.push(
+        // most compatible pixel format:
+        'format=yuv420p',
+
+        // setparams is always needed when converting hdr to sdr:
+        'setparams=color_primaries=bt709:color_trc=bt709:colorspace=bt709',
+      );
+
       const videoFiltersStr = videoFilters.length > 0 ? videoFilters.join(',') : 'null';
       graph.push(`[0:${videoStreamIndex}]${videoFiltersStr}[video]`);
     }
@@ -576,11 +598,6 @@ export function createMediaSourceProcess({ path, videoStreamIndex, audioStreamIn
 
   const videoEncodeArgs = [
     'libx264', '-preset', 'ultrafast', '-tune', 'zerolatency', '-crf', '10',
-
-    // should, in theory, set the private options of x264 or x265 automatically
-    // https://www.reddit.com/r/ffmpeg/comments/jlk2zn/how_to_encode_using_bt709/
-    '-colorspace:v', 'bt709', '-color_primaries:v', 'bt709', '-color_trc:v', 'bt709', '-color_range:v', 'tv',
-    '-pix_fmt:v', 'yuv420p',
   ];
 
   // const videoEncodeArgs = ['h264_videotoolbox', '-b:v', '5M']

src/renderer/src/App.tsx

@@ -75,6 +75,7 @@ import {
   isAbortedError,
   withErrorHandling,
   shootConfetti,
+  isMasBuild,
 } from './util';
 import { toast, errorToast, showPlaybackFailedMessage } from './swal';
 import { adjustRate } from './util/rate-calculator';
@@ -1444,7 +1445,7 @@ function App() {
 
       const existingHtml5FriendlyFile = await findExistingHtml5FriendlyFile(fp, cod);
 
-      const needsAutoHtml5ify = !existingHtml5FriendlyFile && !willPlayerProperlyHandleVideo({ streams: fileMeta.streams, hevcPlaybackSupported }) && validDuration;
+      const needsAutoHtml5ify = !existingHtml5FriendlyFile && !willPlayerProperlyHandleVideo({ streams: fileMeta.streams, hevcPlaybackSupported, isMasBuild }) && validDuration;
 
       console.log('loadMedia', { filePath: fp, customOutDir: cod, projectPath });
 

src/renderer/src/util/streams.ts

@@ -1,7 +1,6 @@
 import invariant from 'tiny-invariant';
 import { FFprobeStream, FFprobeStreamDisposition } from '../../../../ffprobe';
 import { AllFilesMeta, ChromiumHTMLAudioElement, ChromiumHTMLVideoElement, CopyfileStreams, LiteFFprobeStream } from '../types';
-import { isMasBuild } from '../util';
 
 
 // taken from `ffmpeg -codecs`
@@ -368,8 +367,10 @@ export async function doesPlayerSupportHevcPlayback() {
 // so we will detect these codecs and convert to dummy
 // "properly handle" here means either play it back or give a playback error if the video codec is not supported
 // todo maybe improve https://github.com/mifi/lossless-cut/issues/88#issuecomment-1363828563
-export function willPlayerProperlyHandleVideo({ streams, hevcPlaybackSupported }: {
-  streams: FFprobeStream[], hevcPlaybackSupported: boolean,
+export function willPlayerProperlyHandleVideo({ streams, hevcPlaybackSupported, isMasBuild }: {
+  streams: FFprobeStream[],
+  hevcPlaybackSupported: boolean,
+  isMasBuild: boolean,
 }) {
   const realVideoStreams = getRealVideoStreams(streams);
   // If audio-only format, assume all is OK
@@ -378,7 +379,7 @@ export function willPlayerProperlyHandleVideo({ streams, hevcPlaybackSupported }
   // https://github.com/mifi/lossless-cut/issues/2562
   // https://github.com/mifi/lossless-cut/issues/2548
   // https://github.com/electron/electron/issues/47947
-  if (isMasBuild && realVideoStreams.some((s) => s.pix_fmt === 'yuv420p10le' && s.color_space === 'bt2020nc' && s.color_primaries === 'bt2020')) {
+  if (isMasBuild && realVideoStreams.some((s) => s.color_space != null && ['bt2020nc', 'bt2020_ncl', 'bt2020c', 'bt2020_cl'].includes(s.color_space) && s.color_primaries === 'bt2020')) {
     return false;
   }