fix: Исправить баг с масштабированием через VIDEOTOOLBOX ускоритель.

feat: добавлена возможность генерировать видео без звука -m --muted

src/core/encoding.ts

@@ -53,6 +53,7 @@ export async function encodeProfileToMP4(
   codecType: 'h264' | 'av1',
   qualitySettings?: CodecQualitySettings,
   optimizations?: VideoOptimizations,
+  muted: boolean = false,
   decoderAccel?: HardwareAccelerator,
   onProgress?: (percent: number) => void
 ): Promise<string> {
@@ -157,12 +158,14 @@ export async function encodeProfileToMP4(
 
   // Build video filter chain
   const filters: string[] = [];
+  const targetWidth = profile.width;
+  const targetHeight = profile.height;
 
   if (decoderAccel === 'nvenc') {
-    // CUDA path: keep frames on GPU
-    filters.push(`scale_cuda=${profile.width}:${profile.height}`);
+    // CUDA path: вписываем в профиль с сохранением исходного AR
+    filters.push(`scale_cuda=${targetWidth}:${targetHeight}:force_original_aspect_ratio=decrease:force_divisible_by=2`);
   } else {
-    filters.push(`scale=${profile.width}:${profile.height}`);
+    filters.push(`scale=${targetWidth}:${targetHeight}:force_original_aspect_ratio=decrease:force_divisible_by=2`);
   }
   
   // Apply optimizations (for future use)
@@ -178,17 +181,26 @@ export async function encodeProfileToMP4(
     }
   }
 
+  // Центрируем кадр, чтобы браузеры (Firefox/videotoolbox) не игнорировали PAR
+  filters.push(
+    `pad=${targetWidth}:${targetHeight}:(ow-iw)/2:(oh-ih)/2`,
+    'setsar=1'
+  );
+
   args.push('-vf', filters.join(','));
 
-  // Audio encoding
-  // Select optimal bitrate based on source (don't upscale)
-  const targetAudioBitrate = parseInt(profile.audioBitrate) || 256;
-  const optimalAudioBitrate = selectAudioBitrate(sourceAudioBitrate, targetAudioBitrate);
-  args.push('-c:a', 'aac', '-b:a', optimalAudioBitrate);
-  
-  // Audio optimizations
-  if (optimizations?.audioNormalize) {
-    args.push('-af', 'loudnorm');
+  if (!muted) {
+    // Audio encoding
+    const targetAudioBitrate = parseInt(profile.audioBitrate) || 256;
+    const optimalAudioBitrate = selectAudioBitrate(sourceAudioBitrate, targetAudioBitrate);
+    args.push('-c:a', 'aac', '-b:a', optimalAudioBitrate);
+    
+    // Audio optimizations
+    if (optimizations?.audioNormalize) {
+      args.push('-af', 'loudnorm');
+    }
+  } else {
+    args.push('-an'); // без аудио дорожки
   }
 
   // Output
@@ -217,6 +229,7 @@ export async function encodeProfilesToMP4(
   codecType: 'h264' | 'av1',
   qualitySettings?: CodecQualitySettings,
   optimizations?: VideoOptimizations,
+  muted: boolean = false,
   decoderAccel?: HardwareAccelerator,
   onProgress?: (profileName: string, percent: number) => void
 ): Promise<Map<string, string>> {
@@ -239,6 +252,7 @@ export async function encodeProfilesToMP4(
           codecType,
           qualitySettings,
           optimizations,
+          muted,
           decoderAccel,
           (percent) => {
             if (onProgress) {
@@ -269,6 +283,7 @@ export async function encodeProfilesToMP4(
         codecType,
         qualitySettings,
         optimizations,
+        muted,
         decoderAccel,
         (percent) => {
           if (onProgress) {