1.11.0: Encoding with H.265 (Media Foundation) on Qualcomm CPU no longer works

Problem Description

I've used the H.265 (Media Foundation) video encoder previously with 1.10.2 and it worked just fine. After upgrading to 1.11.0, it no longer works and results in:

D3D11: Unsupported filter Comb Detect (id: 4)
...
[hevc_mf @ 000001b5c62fb8e0] MFT name: 'QCOM Hardware Encoder - HEVC'
muxavformat: avformat_write_header failed!
...
[aac @ 000001b5c62fbc60] Ignoring attempt to flush encoder that doesn't support it
[aac @ 000001b5c62fbc60] Qavg: nan
[ac3 @ 000001b5c62fb560] Ignoring attempt to flush encoder that doesn't support it
[hevc_mf @ 000001b5c62fb8e0] Ignoring attempt to flush encoder that doesn't support it
...
 # Job Failed to Initialise. Check log and input settings (3)

Reinstalling 1.10.2 results in everything working as it did before.

Activity Log, Crash Log or any other details

HandBrake 1.11.0 (2026030800)
OS: Microsoft Windows NT 10.0.26200.0
CPU: Snapdragon(R) X 12-core X1E80100 @ 3.40 GHz
Ram: 32327 MB, 
GPU Information:
  Arm Chipset -
Screen: 3440x1440
Temp Dir: C:\Users\me\AppData\Local\Temp\
Install Dir: C:\Program Files\HandBrake\
Data Dir: C:\Users\me\AppData\Roaming\HandBrake

-------------------------------------------

 # Starting Encode ...

[18:36:30] base preset: BluRay MF x265: Constant 85 (8-bit)
[18:36:30] Remote Process started with Process ID: 22332 using port: 8037. Max Allowed Instances: 1
[18:36:30] Worker: Starting HandBrake Engine ...
[18:36:30] Worker: Parent Process Id 19788
[18:36:30] Worker: Starting Web Server on port 8037 ...
[18:36:30] Worker: Starting Listener: 1
[18:36:30] Worker: Server Started
[18:36:30] Worker: Disconnected worker monitoring enabled!
[18:36:30] Compile-time hardening features are enabled
[18:36:30] directx: is available
[18:36:30] hb_init: starting libhb thread

[18:36:30] Starting work at: Sun Mar 15 18:36:30 2026
[18:36:30] 1 job(s) to process
[18:36:30] json job:
{
  "Audio": {
    "AudioList": [
      {
        "Bitrate": 320,
        "DRC": 0,
        "Encoder": "av_aac",
        "Gain": 0,
        "Mixdown": 4,
        "NormalizeMixLevel": false,
        "Samplerate": 0,
        "Name": "Stereo",
        "Track": 0,
        "DitherMethod": 0
      },
      {
        "Bitrate": 640,
        "DRC": 0,
        "Encoder": "ac3",
        "Gain": 0,
        "Mixdown": 7,
        "NormalizeMixLevel": false,
        "Samplerate": 0,
        "Name": "Surround",
        "Track": 0,
        "DitherMethod": 0
      }
    ],
    "CopyMask": [
      "copy:aac",
      "copy:ac3"
    ],
    "FallbackEncoder": "av_aac"
  },
  "Destination": {
    "ChapterList": [
      {
        "Name": "Chapter 1"
      },
      {
        "Name": "Chapter 2"
      },
      {
        "Name": "Chapter 3"
      },
      {
        "Name": "Chapter 4"
      },
      {
        "Name": "Chapter 5"
      },
      {
        "Name": "Chapter 6"
      },
      {
        "Name": "Chapter 7"
      },
      {
        "Name": "Chapter 8"
      },
      {
        "Name": "Chapter 9"
      },
      {
        "Name": "Chapter 10"
      }
    ],
    "ChapterMarkers": true,
    "AlignAVStart": false,
    "File": "F:\\Movies\\MyVideo-1.mkv",
    "Options": {
      "IpodAtom": false,
      "Optimize": true
    },
    "Mux": "av_mkv"
  },
  "Filters": {
    "FilterList": [
      {
        "ID": 6,
        "Settings": {
          "mode": "7"
        }
      },
      {
        "ID": 4,
        "Settings": {
          "block-height": "16",
          "block-thresh": "40",
          "block-width": "16",
          "filter-mode": "2",
          "mode": "3",
          "motion-thresh": "1",
          "spatial-metric": "2",
          "spatial-thresh": "1"
        }
      },
      {
        "ID": 20,
        "Settings": {
          "crop-bottom": "22",
          "crop-left": "0",
          "crop-right": "0",
          "crop-top": "20",
          "height": "1038",
          "width": "1920"
        }
      },
      {
        "ID": 11,
        "Settings": {
          "mode": "0"
        }
      }
    ]
  },
  "PAR": {
    "Num": 1,
    "Den": 1
  },
  "Metadata": {},
  "CoverArts": [],
  "SequenceID": 0,
  "Source": {
    "Angle": 1,
    "Range": {
      "Type": "chapter",
      "Start": 1,
      "End": 10
    },
    "Title": 3,
    "Path": "F:\\Disks\\MyVideo",
    "HWDecode": 16,
    "KeepDuplicateTitles": false
  },
  "Subtitle": {
    "Search": {
      "Burn": false,
      "Default": false,
      "Enable": false,
      "Forced": false
    },
    "SubtitleList": []
  },
  "Video": {
    "Encoder": "mf_h265",
    "Level": "auto",
    "MultiPass": false,
    "Turbo": false,
    "ColorRange": 1,
    "ColorMatrixCode": 0,
    "Options": "",
    "Preset": "default",
    "Profile": "main",
    "Quality": 85,
    "HardwareDecode": 2147483664
  }
}
[18:36:30] OS: Windows 10.0 (26200)
[18:36:30] CPU: Unknown
[18:36:30]  - logical processor count: 12
[18:36:30] hb_scan: path=F:\Disks\MyVideo, title_index=3
[18:36:30] scan: BD has 5 title(s)
[18:36:30] bd: scanning title 3
[18:36:30] bd: playlist 00002.MPLS
[18:36:30] bd: duration is 01:36:33 (5793204 ms)
[18:36:30] bd: video id=0x1011, stream type=H.264, format 1080p
[18:36:30] bd: aspect = 16:9
[18:36:30] bd: audio id=0x711100, lang=English (DTS), 3cc=eng
[18:36:30] bd: audio id=0x1100, lang=English (DTS-HD MA), 3cc=eng
[18:36:30] bd: subtitle id=0x1200, lang=English (PGS), 3cc=eng
[18:36:30] bd: chap 1, 249332 ms
[18:36:31] bd: chap 2, 897855 ms
[18:36:31] bd: chap 3, 477435 ms
[18:36:31] bd: chap 4, 583416 ms
[18:36:31] bd: chap 5, 991407 ms
[18:36:31] bd: chap 6, 395728 ms
[18:36:31] bd: chap 7, 451409 ms
[18:36:31] bd: chap 8, 1204369 ms
[18:36:31] bd: chap 9, 182682 ms
[18:36:31] bd: chap 10, 359067 ms
[18:36:31] bd: chapter 11 too short 521343322, dropping
[18:36:31] bd: title 3 has 10 chapters
[18:36:31] scan: decoding previews for title 3
[18:36:31] scan: title angle(s) 1
[18:36:31] scan: audio 0x711100: dca, rate=48000Hz, bitrate=1536000 English (DTS, 5.1 ch, 1536 kbps)
[18:36:31] scan: audio 0x1100: dca, rate=48000Hz, bitrate=1 English (DTS-HD MA, 5.1 ch)
[18:36:31] using container PAR 1:1
[18:36:31] scan: 10 previews, 1920x1080, 23.976 fps, autocrop = 20/22/0/0, aspect 16:9, PAR 1:1, color profile: 1-1-1, chroma location: left
[18:36:31] scan: supported video decoders: avcodec hwaccel
[18:36:31] stream: 5 good frames, 0 errors (0%)
[18:36:31] libhb: scan thread found 1 valid title(s)
[18:36:31] Starting Task: Encoding Pass
[18:36:31] D3D11: Unsupported filter Comb Detect (id: 4)
[18:36:31] work: track 1, dithering not supported by codec
[18:36:31] work: track 2, dithering not supported by codec
[18:36:31] job configuration:
[18:36:31]  * source
[18:36:31]    + F:\Disks\MyVideo
[18:36:31]    + title 3, chapter(s) 1 to 10
[18:36:31]  * destination
[18:36:31]    + F:\Movies\MyVideo-1.mkv
[18:36:31]    + container: Matroska (libavformat)
[18:36:31]      + chapter markers
[18:36:31]  * video track
[18:36:31]    + decoder: mf hwaccel h264 8-bit (yuv420p, sw)
[18:36:31]      + bitrate 200 kbps
[18:36:31]    + filters
[18:36:31]      + Comb Detect (mode=3:spatial-metric=2:motion-thresh=1:spatial-thresh=1:filter-mode=2:block-thresh=40:block-width=16:block-height=16)
[18:36:31]      + Decomb (mode=39)
[18:36:31]      + Framerate Shaper (mode=0)
[18:36:31]        + frame rate: same as source (around 23.976 fps)
[18:36:31]      + Crop and Scale (width=1920:height=1038:crop-top=20:crop-bottom=22:crop-left=0:crop-right=0)
[18:36:31]        + source: 1920 * 1080, crop (20/22/0/0): 1920 * 1038, scale: 1920 * 1038
[18:36:31]      + Format (format=nv12)
[18:36:31]    + Output geometry
[18:36:31]      + storage dimensions: 1920 x 1038
[18:36:31]      + pixel aspect ratio: 1 : 1
[18:36:31]      + display dimensions: 1920 x 1038
[18:36:31]    + encoder: H.265 (MediaFoundation)
[18:36:31]      + preset:  default
[18:36:31]      + profile: main
[18:36:31]      + level:   auto
[18:36:31]      + quality: 85.00 (Quality)
[18:36:31]      + color profile: 1-1-1
[18:36:31]      + color range: tv
[18:36:31]      + chroma location: left
[18:36:31]  * audio track 1
[18:36:31]    + name: Stereo
[18:36:31]    + decoder: English (DTS, 5.1 ch, 1536 kbps) (track 1, id 0x711100)
[18:36:31]      + bitrate: 1536 kbps, samplerate: 48000 Hz
[18:36:31]    + mixdown: Stereo
[18:36:31]    + encoder: AAC (libavcodec)
[18:36:31]      + bitrate: 320 kbps, samplerate: 48000 Hz
[18:36:31]  * audio track 2
[18:36:31]    + name: Surround
[18:36:31]    + decoder: English (DTS, 5.1 ch, 1536 kbps) (track 1, id 0x711100)
[18:36:31]      + bitrate: 1536 kbps, samplerate: 48000 Hz
[18:36:31]    + mixdown: 5.1 Channels
[18:36:31]    + encoder: AC3 (libavcodec)
[18:36:31]      + bitrate: 640 kbps, samplerate: 48000 Hz
[18:36:31] sync: expecting 138897 video frames
[18:36:31] encavcodecInit: H.265 (MediaFoundation)
[18:36:31] encavcodec: encoding with stored aspect 1/1
[hevc_mf @ 000001b5c62fb8e0] MFT name: 'QCOM Hardware Encoder - HEVC'
muxavformat: avformat_write_header failed!
[18:36:31] work: average encoding speed for job is 0.000000 fps
[18:36:32] comb detect: heavy 0 | light 0 | uncombed 0 | total 0
[18:36:32] vfr: 0 frames output, 0 dropped
[18:36:32] vfr: lost time: 0 (0 frames)
[18:36:32] vfr: gained time: 0 (0 frames) (0 not accounted for)
[18:36:32] dca-decoder done: 0 frames, 0 decoder errors
[18:36:32] dca-decoder done: 0 frames, 0 decoder errors
[18:36:32] h264-decoder done: 0 frames, 0 decoder errors
[18:36:32] sync: got 0 frames, 138897 expected
[aac @ 000001b5c62fbc60] Ignoring attempt to flush encoder that doesn't support it
[aac @ 000001b5c62fbc60] Qavg: nan
[ac3 @ 000001b5c62fb560] Ignoring attempt to flush encoder that doesn't support it
[hevc_mf @ 000001b5c62fb8e0] Ignoring attempt to flush encoder that doesn't support it
[18:36:32] mux: track 0, 0 frames, 0 bytes, 0.00 kbps, fifo 8
[18:36:32] mux: track 1, 0 frames, 0 bytes, 0.00 kbps, fifo 8
[18:36:32] mux: track 2, 0 frames, 0 bytes, 0.00 kbps, fifo 8
[18:36:32] Finished work at: Sun Mar 15 18:36:32 2026
[18:36:32] libhb: work result = 3

 # Job Failed to Initialise. Check log and input settings (3)

What Operating System are you running?

Windows 11 25H2 (26200.8037) (ARM64)

What version of HandBrake are you running?

1.11.0

Where did you download HandBrake from?

No response

No source files or tests are named. Reproduce the failure on Windows ARM64 with the QCOM Hardware Encoder - HEVC and trace the H.265 Media Foundation path through the avformat_write_header failure. Done means the 1.11.0 regression is resolved and the reported encoding job initializes and produces output.