# HDR to SDR Conversion MK.IO Beam supports HDR-to-SDR conversion for decoded video, compressing the dynamic range of HDR content to ensure compatibility with standard dynamic range (SDR) systems. ### Supported HDR formats Conversion is supported for the following HDR formats: - PQ10/HDR10 - HLG10 Inputs in these formats are tone-mapped to SDR, producing an SDR signal with transfer characteristics compliant with BT.709, as defined by the selected tone-mapping _lookup table (LUT)_. ## Configuring HDR to SDR Conversion ### Enabling Dynamic Range Conversion Each _Receiver_ service can be configured for HDR to SDR conversion. Before you start, ensure at least one Receiver service is configured. 1. From the **Home** page, select the **RECEIVER** item from the required feed then click `Edit`. 2. In the **Parameters** window, select the **Output** tab. 3. Configure _HDR-to-SDR conversion_ by setting the **Dynamic Range Conversion** option to one of the following selections: - **None**: HDR-to-SDR conversion is disabled; the video is passed through unchanged - **Custom HDR to BT.709 lookup table**: Use the specified custom LUT to output BT.709 encoded SDR - **Convert to BT.709**: Use proprietary tone-mapping LUT to output BT.709 encoded SDR 4. If _Dynamic Range Conversion_ has been set to **Custom HDR to BT.709 lookup table** then select the required custom LUT description from the **Custom HDR to BT.709 lookup table** drop-down option. ![receiver decoding video hdr to sdr](/_machine-assets/62cd9b5a072ac620985f2f46bc2a32491f0cc284997e4ccfdc117d98546471a0.png) 5. Click **Save and continue** to save your changes. > **Info:** > > - If the incoming stream is already SDR, conversion is automatically bypassed. > - It cannot be verified whether a selected custom LUT is compatible with the > [supported HDR formats](/beam/receiver/output/hdr-sdr#supported-hdr-formats) listed above, so care should be taken when > selecting custom LUTs. > - If an issue occurs during HDR-to-SDR conversion, an alarm is raised. ## HDR to SDR Conversion Lookup Tables HDR-to-SDR conversion uses **3D look-up tables (3D LUTs)**, provided as **.cube** files, to map input RGB values to output RGB values within a three-dimensional grid, enabling complex colour transformations. MK.IO Beam supports **size 33** LUTs. ### Viewing Stored LUTs Multiple LUTs can be stored on MK.IO Beam and individually selected by a _Receiver_ service. The **Stored LUTs** section lists custom LUTs which have been uploaded to the MK.IO Beam device: 1. Select `sliders` icon **Appliance** from the left-hand side menu. 2. Click the **HDR > SDR Conversion** tab. ![hdr sdr conversion tab](/_machine-assets/77fed46835940d423e697558e4466a5fc0256f0b8ea413b324eb10edaf4adc74.png) Each row in the **Stored LUTs** section provides the following information and their current settings. Some settings can be modified and saved using the **Update** button. | Parameter | Description | | :---------------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Description | The reference description given to the custom LUT. This will be listed in the selection when configuring HDR to SDR conversion in the Output settings of a _Receiver_ service. | | Filename | The filename of the **.cube** file that was uploaded. | | Input Full Range | This determines whether **input samples** are processed using the full (EBU R 103) range or the standard (limited) YUV range. | | Output Full Range | This determines whether **output samples** are processed using the full (EBU R 103) range or the standard (limited) YUV range. | | Creation Date | Date and time when the custom LUT was uploaded. | | Last Modified | Data and time when the custom LUT was last modified. | | File CRC | Unique CRC value of the **.cube** file that was uploaded. | | Actions | Possible actions for the custom LUT: - **Update**: Any modifications must be saved by using this button - **Delete**: Delete the custom LUT from the device | ### Built-in LUTs MK.IO Beam includes built-in 3D LUTs. These do not appear in the **Stored LUTs** table on the `sliders` icon **Appliance** pages, but are available for selection when configuring HDR to SDR conversion in the Output settings of a _Receiver_ service. See the [Configuring HDR to SDR Conversion](/beam/receiver/output/hdr-sdr#configuring-hdr-to-sdr-conversion) section for more information. ### Uploading Custom LUTs To upload additional LUTs, follow these steps: 1. Select `sliders` icon **Appliance** from the left-hand side menu. 2. Click the **HDR > SDR Conversion** tab. 3. Select the **Upload LUT** textbox. A file explorer window will appear. 4. Use the file explorer to navigate to the LUT file to upload. Only **.cube** files will be accepted by MK.IO Beam. 5. Click the **Description** testbox to add a unique description of the LUT so that it can be easily referenced when enabling _Dynamic Range Conversion_. 6. Enable or disable the **Input Full Range** setting as required. 7. Enable or disable the **Output Full Range** setting as required. 8. Once the settings are complete, click the **Upload** button to store the custom LUT on the device. ![hdr sdr conversion tab](/_machine-assets/341abe88ca6844746c85836bab21949d8c94773d72f4665733ce5d0c13e01a34.png)