feat(android): add high-speed video recording mode

docs/content/docs/constraints.mdx

@@ -361,6 +361,20 @@ const constraints = [
 ] satisfies Constraint[]
 ```
 
+#### High-speed and slow-motion
+
+On Android, you can request a high-speed capture session with a [`{ videoRecordingMode: ... }`](/api/react-native-vision-camera/interfaces/VideoRecordingModeConstraint) constraint.
+Use `'high-speed'` to save a high frame-rate file directly, or `'slow-motion'` to save the recording with a slow-motion playback effect.
+
+If you do not also provide an explicit [`{ fps: ... }`](/api/react-native-vision-camera/interfaces/FPSConstraint) constraint, VisionCamera automatically picks the lowest supported high-speed FPS for the negotiated session.
+
+```ts
+const constraints = [
+  { videoRecordingMode: 'slow-motion' },
+  { fps: 240 },
+] satisfies Constraint[]
+```
+
 #### Binned preference
 
 Binned formats combine multiple neighboring sensor pixels into one larger effective pixel.

docs/content/docs/fps.mdx

@@ -78,3 +78,18 @@ await session.start()
 ```
 </Tab>
 </Tabs>
+
+### High-speed and Slow-motion
+
+On Android, you can turn a Video recording into a negotiated high-speed capture session by combining your Video output with a [`{ videoRecordingMode: ... }`](/api/react-native-vision-camera/interfaces/VideoRecordingModeConstraint) constraint:
+
+```ts
+const constraints = [
+  { videoRecordingMode: 'slow-motion' },
+  { fps: 240 },
+]
+```
+
+- Use `'high-speed'` to save the file at the negotiated high FPS.
+- Use `'slow-motion'` to record at a high FPS and save the file for slow-motion playback.
+- If you omit the [`{ fps: ... }`](/api/react-native-vision-camera/interfaces/FPSConstraint) constraint, VisionCamera automatically picks the lowest supported high-speed FPS for that session.

packages/react-native-vision-camera/android/src/main/java/com/margelo/nitro/camera/hybrids/HybridCameraSessionConfig.kt

@@ -7,6 +7,7 @@ import com.margelo.nitro.camera.HybridCameraSessionConfigSpec
 import com.margelo.nitro.camera.PixelFormat
 import com.margelo.nitro.camera.TargetDynamicRange
 import com.margelo.nitro.camera.TargetStabilizationMode
+import com.margelo.nitro.camera.VideoRecordingMode
 import com.margelo.nitro.camera.public.NativeCameraOutput
 import com.margelo.nitro.camera.public.NativeCameraSessionConfig
 
@@ -31,6 +32,9 @@ class HybridCameraSessionConfig(
   override val isPhotoHDREnabled: Boolean
     get() = resolvedConfig.photoHDR ?: false
 
+  override val selectedVideoRecordingMode: VideoRecordingMode?
+    get() = resolvedConfig.videoRecordingMode
+
   override val nativePixelFormat: PixelFormat
     // TODO: Do we always stream in PRIVATE?
     get() = PixelFormat.PRIVATE
@@ -52,6 +56,7 @@ class HybridCameraSessionConfig(
         "selectedPreviewStabilizationMode: $selectedPreviewStabilizationMode",
         "selectedVideoDynamicRange: $selectedVideoDynamicRange",
         "isPhotoHDREnabled: $isPhotoHDREnabled",
+        "selectedVideoRecordingMode: $selectedVideoRecordingMode",
       )
     return "CameraSessionConfig(${components.joinToString(", ")})"
   }

packages/react-native-vision-camera/android/src/main/java/com/margelo/nitro/camera/hybrids/outputs/HybridVideoOutput.kt

@@ -2,8 +2,6 @@ package com.margelo.nitro.camera.hybrids.outputs
 
 import android.annotation.SuppressLint
 import android.content.Context
-import android.util.Log
-import androidx.camera.core.DynamicRange
 import androidx.camera.video.FileOutputOptions
 import androidx.camera.video.Recorder
 import androidx.camera.video.VideoCapture
@@ -14,7 +12,6 @@ import com.margelo.nitro.camera.HybridRecorderSpec
 import com.margelo.nitro.camera.MediaType
 import com.margelo.nitro.camera.MirrorMode
 import com.margelo.nitro.camera.RecorderSettings
-import com.margelo.nitro.camera.Size
 import com.margelo.nitro.camera.TargetStabilizationMode
 import com.margelo.nitro.camera.VideoCodec
 import com.margelo.nitro.camera.VideoOutputOptions
@@ -100,8 +97,10 @@ class HybridVideoOutput(
       VideoCapture
         .Builder(videoOutput)
         .apply {
-          // isMirrored={...}
-          setMirrorMode(mirrorMode.toMirrorMode())
+          if (config.videoRecordingMode == null) {
+            // High-speed sessions cannot set mirror mode on VideoCapture.
+            setMirrorMode(mirrorMode.toMirrorMode())
+          }
           // orientation from previous value
           setTargetRotation(outputOrientation.surfaceRotation)
 

packages/react-native-vision-camera/android/src/main/java/com/margelo/nitro/camera/public/NativeCameraOutput.kt

@@ -5,6 +5,7 @@ import androidx.camera.core.UseCase
 import com.margelo.nitro.camera.MirrorMode
 import com.margelo.nitro.camera.TargetDynamicRange
 import com.margelo.nitro.camera.TargetStabilizationMode
+import com.margelo.nitro.camera.VideoRecordingMode
 
 interface NativeCameraOutput {
   /**
@@ -17,6 +18,7 @@ interface NativeCameraOutput {
     val videoStabilizationMode: TargetStabilizationMode?,
     val videoDynamicRange: TargetDynamicRange?,
     val photoHDR: Boolean?,
+    val videoRecordingMode: VideoRecordingMode?,
   )
 
   /**

packages/react-native-vision-camera/android/src/main/java/com/margelo/nitro/camera/session/ConstraintResolver.kt

@@ -6,7 +6,9 @@ import androidx.camera.core.CameraInfo
 import androidx.camera.core.ImageCapture
 import androidx.camera.core.Preview
 import androidx.camera.core.SessionConfig
+import androidx.camera.video.HighSpeedVideoSessionConfig
 import androidx.camera.video.Recorder
+import androidx.camera.video.VideoCapture
 import com.margelo.nitro.camera.CameraOutputConfiguration
 import com.margelo.nitro.camera.Constraint
 import com.margelo.nitro.camera.FPSConstraint
@@ -17,6 +19,8 @@ import com.margelo.nitro.camera.TargetDynamicRange
 import com.margelo.nitro.camera.TargetDynamicRangeBitDepth
 import com.margelo.nitro.camera.TargetStabilizationMode
 import com.margelo.nitro.camera.VideoDynamicRangeConstraint
+import com.margelo.nitro.camera.VideoRecordingMode
+import com.margelo.nitro.camera.VideoRecordingModeConstraint
 import com.margelo.nitro.camera.VideoStabilizationModeConstraint
 import com.margelo.nitro.camera.extensions.converters.toDynamicRange
 import com.margelo.nitro.camera.public.NativeCameraOutput
@@ -67,23 +71,19 @@ object ConstraintResolver {
           return@map output.createUseCase(outputConfiguration.mirrorMode, config)
         }
       val sessionConfig =
-        SessionConfig
-          .Builder(preparedUseCases.map { it.useCase })
-          .build()
+        buildSessionConfig(cameraInfo, preparedUseCases, config)
 
-      if (cameraInfo.isSessionConfigSupported(sessionConfig) || activeConstraints.isEmpty()) {
+      if (sessionConfig != null && (cameraInfo.isSessionConfigSupported(sessionConfig) || activeConstraints.isEmpty())) {
         // Pass 2: Resolve FPS against the validated use-case combination.
-        val resolvedFPSRange = fpsConstraint?.resolveFPSRange(cameraInfo, sessionConfig)
+        val resolvedFPSRange =
+          resolveFPSRange(
+            cameraInfo = cameraInfo,
+            sessionConfig = sessionConfig,
+            targetFps = fpsConstraint?.fps?.toInt(),
+            shouldAutoSelectLowest = config.videoRecordingMode != null,
+          )
         val finalConfig = config.copy(fpsRange = resolvedFPSRange)
-        val finalSessionConfig =
-          if (resolvedFPSRange != null) {
-            SessionConfig
-              .Builder(preparedUseCases.map { it.useCase })
-              .apply { setFrameRateRange(resolvedFPSRange) }
-              .build()
-          } else {
-            sessionConfig
-          }
+        val finalSessionConfig = buildSessionConfig(cameraInfo, preparedUseCases, finalConfig) ?: sessionConfig
         Log.i(TAG, "Resolved constraints to: $finalConfig")
         return CameraSessionConfig(finalSessionConfig, preparedUseCases, finalConfig)
       }
@@ -109,13 +109,20 @@ object ConstraintResolver {
    * Picks the supported range whose upper bound is closest to the target FPS.
    * On ties, prefers tighter ranges (higher lower bound).
    */
-  private fun FPSConstraint.resolveFPSRange(
+  private fun resolveFPSRange(
     cameraInfo: CameraInfo,
     sessionConfig: SessionConfig,
+    targetFps: Int?,
+    shouldAutoSelectLowest: Boolean,
   ): Range<Int>? {
-    val targetFps = fps.toInt()
     val supportedRanges = cameraInfo.getSupportedFrameRateRanges(sessionConfig)
     if (supportedRanges.isEmpty()) return null
+    if (targetFps == null) {
+      if (!shouldAutoSelectLowest) return null
+      return supportedRanges.minWith(
+        compareBy<Range<Int>> { it.upper }.thenBy { it.lower },
+      )
+    }
 
     return supportedRanges.minWith(
       compareBy<Range<Int>> {
@@ -127,6 +134,49 @@ object ConstraintResolver {
       },
     )
   }
+
+  private fun buildSessionConfig(
+    cameraInfo: CameraInfo,
+    preparedUseCases: List<NativeCameraOutput.PreparedUseCase>,
+    config: NativeCameraOutput.Config,
+  ): SessionConfig? {
+    return when (config.videoRecordingMode) {
+      null -> {
+        SessionConfig
+          .Builder(preparedUseCases.map { it.useCase })
+          .apply {
+            config.fpsRange?.let { setFrameRateRange(it) }
+          }.build()
+      }
+      else -> buildHighSpeedSessionConfig(cameraInfo, preparedUseCases, config)
+    }
+  }
+
+  private fun buildHighSpeedSessionConfig(
+    cameraInfo: CameraInfo,
+    preparedUseCases: List<NativeCameraOutput.PreparedUseCase>,
+    config: NativeCameraOutput.Config,
+  ): SessionConfig? {
+    if (Recorder.getHighSpeedVideoCapabilities(cameraInfo) == null) return null
+
+    val previewUseCases = preparedUseCases.mapNotNull { it.useCase as? Preview }
+    val videoCaptureUseCases = preparedUseCases.mapNotNull { it.useCase as? VideoCapture<*> }
+    val containsUnsupportedUseCases =
+      preparedUseCases.any { preparedUseCase ->
+        preparedUseCase.useCase !is Preview && preparedUseCase.useCase !is VideoCapture<*>
+      }
+    if (containsUnsupportedUseCases || videoCaptureUseCases.size != 1 || previewUseCases.size > 1) {
+      return null
+    }
+
+    return HighSpeedVideoSessionConfig
+      .Builder(videoCaptureUseCases.single())
+      .apply {
+        previewUseCases.singleOrNull()?.let { setPreview(it) }
+        setSlowMotionEnabled(config.videoRecordingMode == VideoRecordingMode.SLOW_MOTION)
+        config.fpsRange?.let { setFrameRateRange(it) }
+      }.build()
+  }
 }
 
 // MARK: - Config Resolution
@@ -138,7 +188,7 @@ object ConstraintResolver {
  * constraint are `null`, meaning "platform decides".
  *
  * FPS is not resolved here — it requires a validated [SessionConfig]
- * and is resolved separately in [FPSConstraint.resolveFPSRange].
+ * and is resolved separately in [ConstraintResolver.resolveConstraints].
  */
 internal fun List<Constraint>.toConfig(): NativeCameraOutput.Config {
   return NativeCameraOutput.Config(
@@ -147,6 +197,7 @@ internal fun List<Constraint>.toConfig(): NativeCameraOutput.Config {
     videoStabilizationMode = firstNotNullOfOrNull { it.asType<VideoStabilizationModeConstraint>() }?.videoStabilizationMode,
     videoDynamicRange = firstNotNullOfOrNull { it.asType<VideoDynamicRangeConstraint>() }?.videoDynamicRange,
     photoHDR = firstNotNullOfOrNull { it.asType<PhotoHDRConstraint>() }?.photoHDR,
+    videoRecordingMode = firstNotNullOfOrNull { it.asType<VideoRecordingModeConstraint>() }?.videoRecordingMode,
   )
 }
 
@@ -161,7 +212,9 @@ internal fun List<Constraint>.toConfig(): NativeCameraOutput.Config {
  * When in doubt, returns `true` — a constraint that wrongly returns `false`
  * is silently dropped with no chance of recovery.
  */
-private fun Constraint.isSupportedIndividually(cameraInfo: CameraInfo): Boolean {
+private fun Constraint.isSupportedIndividually(
+  cameraInfo: CameraInfo,
+): Boolean {
   return this.match(
     { true }, // FPS: resolved separately after features
     { videoStabilizationMode ->
@@ -195,6 +248,7 @@ private fun Constraint.isSupportedIndividually(cameraInfo: CameraInfo): Boolean
     },
     { true }, // PixelFormat: let downgrade loop handle it
     { true }, // Binning: not configurable in CameraX
+    { Recorder.getHighSpeedVideoCapabilities(cameraInfo) != null },
   )
 }
 
@@ -261,5 +315,6 @@ private fun Constraint.getNextBestOption(): Constraint? {
     { null }, // PhotoHDR: on or off, no middle ground
     { null }, // PixelFormat: no fallback
     { null }, // Binning: not configurable
+    { null }, // VideoRecordingMode: falls back to regular recording
   )
 }

packages/react-native-vision-camera/ios/Hybrid Objects/Constraints/ConstraintResolver.swift

@@ -126,7 +126,8 @@ enum ConstraintResolver {
       selectedFPS: fps,
       selectedVideoStabilizationMode: videoStabilizationMode,
       selectedPreviewStabilizationMode: previewStabilizationMode,
-      selectedVideoDynamicRange: videoDynamicRange)
+      selectedVideoDynamicRange: videoDynamicRange,
+      selectedVideoRecordingMode: nil)
 
     return FormatEvaluation(
       format: format,
@@ -238,6 +239,9 @@ extension Constraint {
     case .eigth(let binned):
       let r = binned.resolve(for: format)
       return ConstraintEvaluation(penalty: r.penalty, resolved: .formatOnly)
+    case .ninth( /* videoRecordingMode */ _):
+      // High-speed session orchestration is currently Android-only.
+      return ConstraintEvaluation(penalty: .noPenalty, resolved: .formatOnly)
     }
   }
 }

packages/react-native-vision-camera/ios/Hybrid Objects/Constraints/EnabledConstraints.swift

@@ -13,4 +13,5 @@ public struct EnabledConstraints {
   let selectedVideoStabilizationMode: TargetStabilizationMode?
   let selectedPreviewStabilizationMode: TargetStabilizationMode?
   let selectedVideoDynamicRange: TargetDynamicRange?
+  let selectedVideoRecordingMode: VideoRecordingMode?
 }

packages/react-native-vision-camera/ios/Hybrid Objects/Constraints/HybridCameraSessionConfig.swift

@@ -38,6 +38,10 @@ final class HybridCameraSessionConfig: HybridCameraSessionConfigSpec, NativeCame
     return negotiatedFormat.format.isHighestPhotoQualitySupported
   }
 
+  var selectedVideoRecordingMode: VideoRecordingMode? {
+    return enabledConstraints.selectedVideoRecordingMode
+  }
+
   var nativePixelFormat: PixelFormat {
     let format = negotiatedFormat.format
     return PixelFormat(mediaSubType: format.formatDescription.mediaSubType)
@@ -60,6 +64,7 @@ final class HybridCameraSessionConfig: HybridCameraSessionConfigSpec, NativeCame
       "selectedPreviewStabilizationMode: \(String(describing: selectedPreviewStabilizationMode))",
       "selectedVideoDynamicRange: \(String(describing: selectedVideoDynamicRange))",
       "isPhotoHDREnabled: \(isPhotoHDREnabled)",
+      "selectedVideoRecordingMode: \(String(describing: selectedVideoRecordingMode))",
     ]
     return "CameraSessionConfig(\(components.joined(separator: ", ")))"
   }