The feature should utilize the zscale or tonemap_opencl (for hardware acceleration) video filters in the encoding pipeline.
Proposed Filter Chain (FFmpeg equivalent): If the user checks "Enable Tone Mapping" with BT.2390 algorithm:
zscale=t=linear:npl=100,tonemap=bt2390:desat=0,zscale=t=bt709:m=bt709:r=tv
Hardware Acceleration Support:
Scenario A: The Archiver User has a 4K Blu-ray rip of Dune (HDR10). They want a smaller version for their iPad (Non-HDR).
Scenario B: The Fixer User has a video file that is flagged as HDR but looks wrong on their TV. convert hdr to sdr handbrake
Now you are encoding the converted color data.
Same as source and check "Constant Framerate."
2.1 The Challenge HDR video (such as HDR10) utilizes a wider color gamut (BT.2020) and a higher peak brightness (often 1000+ nits) compared to SDR (BT.709, 100 nits). Simply stripping HDR metadata results in a washed-out, desaturated image because SDR screens cannot interpret the extended range of brightness and color.
2.2 The Solution: Tone Mapping
To convert HDR to SDR correctly, the software must perform Tone Mapping. This process compresses the wide dynamic range of the HDR source into the narrower range of SDR. HandBrake utilizes the zimg library to perform this conversion, specifically mapping the BT.2020 color space to BT.709.
HandBrake provides a robust and user-friendly method for converting HDR content to SDR. By utilizing the Colorspace: SDR (BT.709) filter setting, users can ensure their video is playable on legacy hardware and standard monitors without the "washed out" look typical of improper conversions. For most consumer needs, this method balances quality and ease of use perfectly. The feature should utilize the zscale or tonemap_opencl
Prepared by: Technical Assistance Unit
Converting HDR (High Dynamic Range) video to SDR (Standard Dynamic Range) in
is essential if your playback device doesn't support HDR or if the colors look "washed out" on a standard monitor. To get natural-looking colors, you must use HandBrake’s Tone Mapping feature. Here is the direct way to set it up: HandBrake HDR to SDR Settings Load your Source : Open your HDR video file in HandBrake. Select a Preset : Choose a standard preset (e.g., Fast 1080p30 HQ 1080p30 Video Encoder H.264 (x264) H.265 (x265)
select a "10-bit" encoder unless you want to keep the file size large; standard 8-bit is typical for SDR. Filters Tab : Look for the HDR Tone Mapping Select "BT.709" Hardware Acceleration Support: Scenario A: The Archiver User
: This is the standard color space for SDR. This step is the "magic" that prevents the video from looking grey and dull. Audio/Subtitles : Adjust your tracks as needed and click Start Encode Why Tone Mapping Matters
HDR video contains metadata for high brightness and wide color gamuts (like BT.2020). If you simply compress it without tone mapping, an SDR screen won't know how to interpret those extra-bright pixels, resulting in a flat, desaturated image. HandBrake’s tone mapper "squashes" that range into the BT.709 space while trying to preserve as much detail as possible. Pro Tips for Best Results Use the Preview : Before committing to a long encode, use the
button to see a 30-second clip. If the colors still look off, check that "HDR Tone Mapping" is definitely set to HandBrake Version : Ensure you are using Version 1.3.0 or later , as older versions lacked robust tone mapping support. Performance
: Tone mapping adds extra processing work, so expect the encode to take slightly longer than a standard SDR-to-SDR conversion. before you start?