Limit the maximum bitrate of video previews

FreeFeed · Jan 29, 2025 · 57108d8 · 57108d8
1 parent d04ed16
commit 57108d8
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Showing 4 changed files with 22 additions and 3 deletions.
diff --git a/app/support/media-files/detect.ts b/app/support/media-files/detect.ts
@@ -99,6 +99,7 @@ export async function detectMediaType(
           vCodec: videoStream.codec_name,
           aCodec: audioStream?.codec_name,
           duration: parseFloat(format.duration),
+          bitrate: parseInt(format.bit_rate),
           width,
           height,
           h264info,
@@ -146,6 +147,7 @@ async function detectAnimatedImage(
       width: videoStream.width!,
       height: videoStream.height!,
       duration: parseFloat(format.duration),
+      bitrate: parseInt(format.bit_rate),
       isAnimatedImage: true,
     };
   }

diff --git a/app/support/media-files/process.ts b/app/support/media-files/process.ts
@@ -358,6 +358,9 @@ async function processVideo(
     stillFile,
   );
 
+  // Bitrate per pixel of the original video
+  const originalBpp = info.bitrate / (info.width * info.height);
+
   for (const { variant, width, height } of previewSizes) {
     if (variant === maxVariant) {
       if (!canUseOriginalVideo) {
@@ -384,13 +387,17 @@ async function processVideo(
         targetFile,
       );
     } else {
+      const bitrateK = Math.round((1.5 * (originalBpp * (width * height))) / 1000);
       commands.push(
         ['-map', `[${variant}out]`],
         ['-c:v', 'libx264'],
         ['-preset', 'slow'],
         ['-profile:v', 'high'],
         ['-crf', '23'],
-        ['-g', '60'], // For better seeking performance
+        // For better seeking performance
+        ['-g', '60'],
+        // Limit the maximum bitrate
+        info.isAnimatedImage ? [] : ['-maxrate', `${bitrateK}k`, '-bufsize', `${2 * bitrateK}k`],
         ['-pix_fmt', 'yuv420p'],
         ...commonCommands,
         targetFile,

diff --git a/app/support/media-files/types.ts b/app/support/media-files/types.ts
@@ -33,6 +33,7 @@ export type MediaInfoVideo = {
   aCodec?: string;
   isAnimatedImage?: true;
   h264info?: H264Info;
+  bitrate: number;
 } & MediaInfoVisual &
   MediaInfoPlayable &
   MediaInfoCommon;
@@ -109,7 +110,12 @@ export type AvcStream = Stream & {
 };
 
 export type FfprobeResult = {
-  format: { format_name: string; duration: string; tags?: Record<string, string> };
+  format: {
+    format_name: string;
+    duration: string;
+    bit_rate: string;
+    tags?: Record<string, string>;
+  };
   streams: Stream[];
 };
 

diff --git a/test/fixtures/media-files/file-info.json b/test/fixtures/media-files/file-info.json
@@ -9,7 +9,8 @@
       "height": 256,
       "duration": 7.6,
       "isAnimatedImage": true,
-      "extension": "gif"
+      "extension": "gif",
+      "bitrate": 391272
     }
   },
   {
@@ -77,6 +78,7 @@
       "width": 1280,
       "height": 720,
       "duration": 5.005,
+      "bitrate": 1711589,
       "tags": {
         "title": "Kreuz-Polka",
         "major_brand": "isom",
@@ -98,6 +100,7 @@
       "width": 1280,
       "height": 720,
       "duration": 4.993,
+      "bitrate": 2942024,
       "extension": "ogv"
     }
   },
@@ -111,6 +114,7 @@
       "width": 1280,
       "height": 720,
       "duration": 5.237,
+      "bitrate": 1472789,
       "tags": { "encoder": "Lavf58.29.100" },
       "extension": "wmv"