Better compatibility with Dolby vision (#402)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Author: XChikuX

CLAUDE.md

@@ -0,0 +1,126 @@
+# CLAUDE.md
+
+Guidance for AI agents (Claude, Copilot, etc.) and new contributors working in
+this repository. Keep this file up to date when project structure, conventions,
+or workflows change.
+
+## What this project is
+
+`react-native-compressor` is a React Native library that compresses **video**,
+**image**, and **audio** files (and provides background upload/download helpers)
+with results comparable to WhatsApp-style compression. It ships native code for
+both **iOS** (Swift/Obj-C) and **Android** (Kotlin), exposed to JavaScript through
+a TurboModule-capable spec, and supports both the old and new React Native
+architectures plus an Expo config plugin.
+
+- Package name: `react-native-compressor`
+- Package manager: **Yarn 4** (`packageManager: yarn@4.14.1`); Yarn workspaces with `examples/*`.
+- Upstream: https://github.com/numandev1/react-native-compressor — this is a fork
+  (`XChikuX/react-native-compressor`) that triages and fixes upstream issues.
+
+## Repository layout
+
+```
+src/                       JavaScript/TypeScript public API (the npm entry point)
+  index.tsx                Re-exports the public surface
+  Main.tsx                 Aggregates the default export object
+  Spec/NativeCompressor.ts TurboModule spec (single source of truth for native methods)
+  Video/ Image/ Audio/     Per-domain JS wrappers (compress(), options, events)
+  utils/                   Uploader/Downloader/helpers (uuid, path normalization)
+  expo-plugin/             Expo config plugin
+ios/                       Native iOS implementation (Swift + Obj-C bridge)
+  Video/VideoMain.swift            Video compression entry (auto/manual helpers)
+  Video/NextLevelSessionExporter.swift  AVAssetReader/Writer export engine
+  Image/ Audio/ Utils/             Image, audio, upload/download, thumbnails
+  Compressor.mm / Compressor.h     Obj-C bridge to the Swift module
+android/                   Native Android implementation (Kotlin)
+  src/main/java/com/reactnativecompressor/
+    Video/                 Video compression (MediaCodec transcode pipeline)
+      VideoCompressor/compressor/Compressor.kt  Core encode/decode loop
+      VideoCompressor/utils/CompressorUtils.kt  Format/codec helpers
+    Image/ Audio/ Utils/   Image, audio, upload/download, helpers
+  src/oldarch / src/newarch  Architecture-specific TurboModule specs
+__tests__/                 Jest unit tests for the JS wrapper (native is mocked)
+harness/                   react-native-harness on-device smoke test definitions
+examples/bare              Bare React Native example app (build + harness target)
+examples/expo              Expo example app
+TRIAGE.md                  Running triage of upstream issues and fixes in this fork
+```
+
+## Public API surface
+
+The default export aggregates these modules/functions (see
+`__tests__/compressor.test.ts` for the authoritative list):
+`Audio`, `Image`, `Video`, `UploadType`, `UploaderHttpMethod`, `backgroundUpload`,
+`cancelUpload`, `clearCache`, `createVideoThumbnail`, `download`,
+`generateFilePath`, `getDetails`, `getFileSize`, `getImageMetaData`,
+`getRealPath`, `getVideoMetaData`, `uuidv4`.
+
+Video compression supports `compressionMethod: 'auto' | 'manual'`, `maxSize`,
+`bitrate`, `progressDivider`, `minimumFileSizeForCompress`, and `stripAudio`.
+
+## Build, test, and validate
+
+Run JS-level checks from the repo root:
+
+| Command | Purpose |
+| --- | --- |
+| `yarn install` | Install dependencies (Yarn 4) |
+| `yarn jest` / `yarn test` | Run the JS wrapper unit tests |
+| `yarn typecheck` | `tsc --noEmit` |
+| `yarn lint` | ESLint over `**/*.{js,ts,tsx}` |
+| `yarn test:pr` | `test --runInBand && typecheck && lint` (run before opening a PR) |
+| `yarn build:android` | Assemble the bare example (`arm64-v8a`) |
+| `yarn build:ios` | Build the bare example for the iOS simulator |
+| `yarn test:harness:android` / `yarn test:harness:ios` | On-device/simulator smoke tests |
+
+**Important:** The Jest tests mock the native module, so they validate only the
+JS contract. Real media decoding/encoding **cannot** be verified by unit tests —
+it must be smoke-tested in the example app on a simulator or device. When you
+change native Swift/Kotlin code, state clearly that it was not runtime-verified
+in CI and, where possible, validate via the example app or harness.
+
+## Native video pipeline notes (high-signal, easy to get wrong)
+
+### iOS (`ios/Video/`)
+- `VideoMain.swift` builds the `videoOutputConfiguration` / `compressionDict`
+  and drives `NextLevelSessionExporter`.
+- `NextLevelSessionExporter.setupVideoOutput` only creates the video writer input
+  when `writer.canApply(outputSettings:forMediaType:) == true`; otherwise it logs
+  `"Unsupported output configuration"` and writes **audio only**, yet still ends
+  as `.completed`. That means a bad `videoOutputConfiguration` can silently yield
+  an **audio-only** MP4 reported as success.
+- Do **not** add undocumented H.264 (`avc1`) compression properties such as
+  `AVVideoExpectedSourceFrameRateKey` or `AVVideoAverageNonDroppableFrameRateKey`:
+  `canApply(...)` accepts them but the iOS encoder drops the video track
+  (regression in #392, fixed for #400). After export, verify the output asset
+  actually contains a video track before resolving success.
+
+### Android (`android/.../Video/VideoCompressor/`)
+- `Compressor.kt` runs an `MediaExtractor` → decoder (Surface) → encoder
+  (`video/avc`) → `MP4Builder` transcode loop.
+- The decoder is created from the **input** track's MIME. Some containers (notably
+  iPhone `.MOV`) report `video/dolby-vision`, which fails with `NAME_NOT_FOUND`
+  on devices lacking a Dolby Vision decoder. `CompressorUtils.ensureDecodableVideoFormat`
+  remaps such inputs to their backward-compatible HEVC/AVC base layer (profiles 8/4
+  → HEVC, profile 9 → AVC) or throws a clear error for non-compatible profiles
+  (5/7). See #398.
+- The encoder is intentionally `c2.android.avc.encoder` (when QTI codecs exist) or
+  `MediaCodec.createEncoderByType("video/avc")`; QTI AVC encoders can produce MP4s
+  that do not play on Mac/iPhone, so avoid switching this without testing.
+
+## Conventions
+
+- Keep changes surgical and aligned with surrounding style. Native helper objects
+  (e.g. `CompressorUtils`) use member imports and unqualified calls in
+  `Compressor.kt` — match that.
+- When fixing an upstream issue, record it in `TRIAGE.md` (triage row + the
+  "Minor fixes made in this branch" list) referencing the issue number.
+- Prefer graceful, descriptive failures over cryptic native crashes for
+  unsupported media (clear error messages that tell the user what happened).
+
+## Merging back upstream
+
+This fork accumulates many incremental commits. When contributing back to
+`numandev1/react-native-compressor`, use a **squash merge** so the history lands
+as a single, well-described commit rather than the full incremental series.

TRIAGE.md

@@ -13,6 +13,8 @@ Legend:
 
 | Issue | Triage | Notes |
 | --- | --- | --- |
+| #400 | real, fixed here | iOS regression from #392: H.264 `videoOutputConfiguration` added `AVVideoExpectedSourceFrameRateKey` / `AVVideoAverageNonDroppableFrameRateKey`, which `canApply(...)` accepts but the iOS encoder silently drops the video track for, yielding an audio-only MP4 reported as success. This branch removes those keys and verifies the exported file actually contains a video track. |
+| #398 | real, fixed here | Android could not compress Dolby Vision `.MOV` inputs (iPhone HDR): `MediaCodec.createDecoderByType("video/dolby-vision")` fails with `NAME_NOT_FOUND` on devices without a Dolby Vision decoder. This branch remaps the input to its backward-compatible HEVC/AVC base layer when possible, and otherwise fails with a clear, actionable error. |
 | #390 | not a bug | Reports `start` / `end` time behavior for video compression, but the current public video API does not expose trim parameters. |
 | #387 | needs info | Gradle binary store corruption looks environment-specific; report does not isolate a library code change. |
 | #384 | needs info | Performance question, not a reproducible defect report. |
@@ -86,7 +88,9 @@ These should be closed upstream unless a current repro still exists on the lates
 - Android: clamp metadata parsing and reject invalid transcode output
 - Android: adaptive video compression profile for high-resolution inputs
 - Android: fast-start compressed MP4 outputs and skip unsupported copied audio sample metadata
+- Android: decode the backward-compatible base layer of Dolby Vision `.MOV` inputs, or fail with a clear error (#398)
 - Android/iOS: clamp image and thumbnail JPEG quality values
 - Android/iOS: harden thumbnail frame extraction for difficult source videos
 - iOS: guard missing video tracks and use the same adaptive sizing/bitrate strategy
+- iOS: drop unsupported H.264 frame-rate keys and verify the output has a video track to prevent silent audio-only results (#400)
 - iOS: return background-upload response bodies consistently

android/src/main/java/com/reactnativecompressor/Video/VideoCompressor/compressor/Compressor.kt

@@ -11,6 +11,7 @@ import android.net.Uri
 import android.os.Build
 import android.util.Log
 import com.reactnativecompressor.Video.VideoCompressor.CompressionProgressListener
+import com.reactnativecompressor.Video.VideoCompressor.utils.CompressorUtils.ensureDecodableVideoFormat
 import com.reactnativecompressor.Video.VideoCompressor.utils.CompressorUtils.findTrack
 import com.reactnativecompressor.Video.VideoCompressor.utils.CompressorUtils.hasQTI
 import com.reactnativecompressor.Video.VideoCompressor.utils.CompressorUtils.prepareVideoHeight
@@ -790,6 +791,10 @@ object Compressor {
     ): MediaCodec {
         val originalMime = inputFormat.getString(MediaFormat.KEY_MIME)!!
 
+        // Some inputs (e.g. iPhone .MOV files) report a "video/dolby-vision" MIME
+        // type that many devices cannot decode. Remap to a decodable base-layer
+        // codec, or fail with a clear error, before creating the decoder (#398).
+        ensureDecodableVideoFormat(inputFormat)
         // Dolby Vision (video/dolby-vision) has no standalone decoder on most Android
         // devices and throws NAME_NOT_FOUND. Profiles 8.1/8.4 carry an HEVC base layer
         // that the standard HEVC decoder can render, so we remap them to HEVC. Profile 5

android/src/main/java/com/reactnativecompressor/Video/VideoCompressor/utils/CompressorUtils.kt

@@ -207,4 +207,76 @@ object CompressorUtils {
     }
     return false
   }
+
+  // MIME type reported by MediaExtractor for Dolby Vision tracks (e.g. iPhone .MOV files)
+  private const val MIMETYPE_VIDEO_DOLBY_VISION = "video/dolby-vision"
+
+  /**
+   * Check whether the device exposes a decoder for the given MIME type.
+   */
+  private fun hasDecoderForMime(mime: String): Boolean {
+    val codecList = MediaCodecList(MediaCodecList.REGULAR_CODECS)
+    for (codec in codecList.codecInfos) {
+      if (codec.isEncoder) continue
+      for (type in codec.supportedTypes) {
+        if (type.equals(mime, ignoreCase = true)) return true
+      }
+    }
+    return false
+  }
+
+  /**
+   * Resolve the backward-compatible base-layer MIME type for a Dolby Vision track.
+   *
+   * Dolby Vision profiles 8.x (DvheSt) and 4 (DvheDtr) carry an HEVC base layer, and
+   * profile 9 (DvavSe) carries an AVC base layer; these can be decoded by the standard
+   * HEVC/AVC decoders. Profiles 5 (DvheStn) and 7 (DvheDtb) have no usable single base
+   * layer, so they return null. When the profile is unknown we assume HEVC, which covers
+   * the common consumer case (e.g. iPhone records Dolby Vision profile 8).
+   */
+  private fun dolbyVisionBaseLayerMime(inputFormat: MediaFormat): String? {
+    if (!inputFormat.containsKey(MediaFormat.KEY_PROFILE)) {
+      return MediaFormat.MIMETYPE_VIDEO_HEVC
+    }
+    return when (inputFormat.getInteger(MediaFormat.KEY_PROFILE)) {
+      MediaCodecInfo.CodecProfileLevel.DolbyVisionProfileDvavSe -> MediaFormat.MIMETYPE_VIDEO_AVC
+      MediaCodecInfo.CodecProfileLevel.DolbyVisionProfileDvheSt,
+      MediaCodecInfo.CodecProfileLevel.DolbyVisionProfileDvheDtr -> MediaFormat.MIMETYPE_VIDEO_HEVC
+      else -> null
+    }
+  }
+
+  /**
+   * Ensure the input video format can be decoded on this device.
+   *
+   * Some containers (notably iPhone `.MOV` files) expose the video track as
+   * `video/dolby-vision`. Many Android devices have no Dolby Vision decoder, so
+   * `MediaCodec.createDecoderByType("video/dolby-vision")` fails with NAME_NOT_FOUND.
+   * When the dedicated decoder is missing but the stream carries a backward-compatible
+   * base layer, this rewrites the format MIME to the base-layer codec so the standard
+   * HEVC/AVC decoder can decode it. If no compatible decoder exists, it throws a clear
+   * error instead of letting the cryptic native failure surface (see issue #398).
+   */
+  fun ensureDecodableVideoFormat(inputFormat: MediaFormat) {
+    val mime = inputFormat.getString(MediaFormat.KEY_MIME) ?: return
+    if (hasDecoderForMime(mime)) return
+
+    if (mime.equals(MIMETYPE_VIDEO_DOLBY_VISION, ignoreCase = true)) {
+      val fallbackMime = dolbyVisionBaseLayerMime(inputFormat)
+      if (fallbackMime != null && hasDecoderForMime(fallbackMime)) {
+        Log.w(
+          "Compressor",
+          "No Dolby Vision decoder on this device; decoding the $fallbackMime base layer instead."
+        )
+        inputFormat.setString(MediaFormat.KEY_MIME, fallbackMime)
+        return
+      }
+      throw IllegalStateException(
+        "This video uses Dolby Vision, which is not supported by this device's decoders " +
+          "and has no backward-compatible base layer to fall back to."
+      )
+    }
+
+    throw IllegalStateException("No decoder available for video format: $mime")
+  }
 }

ios/Video/VideoMain.swift

@@ -320,11 +320,15 @@ class VideoCompressor {
         exporter.outputURL = tmpURL
         exporter.outputFileType = AVFileType.mp4
 
+        // NOTE: Do not add AVVideoExpectedSourceFrameRateKey or
+        // AVVideoAverageNonDroppableFrameRateKey here. They are not documented
+        // H.264 (avc1) compression properties on iOS and, while AVFoundation's
+        // `canApply(...)` check still returns true, the iOS encoder silently
+        // drops the video track, producing an audio-only MP4 that still reports
+        // success. See issue #400.
         let compressionDict: [String: Any] = [
           AVVideoAverageBitRateKey: bitRate,
           AVVideoProfileLevelKey: AVVideoProfileLevelH264HighAutoLevel,
-          AVVideoExpectedSourceFrameRateKey: frameRate,
-          AVVideoAverageNonDroppableFrameRateKey: frameRate,
         ]
         exporter.optimizeForNetworkUse = true;
         exporter.videoOutputConfiguration = [
@@ -366,7 +370,16 @@ class VideoCompressor {
             switch result {
             case .success:
               if let outputURL = exporter.outputURL {
-                onCompletion(outputURL)
+                // Guard against the iOS encoder silently dropping the video track
+                // and producing an audio-only file that still reports success.
+                // See issue #400.
+                let outputAsset = AVAsset(url: outputURL)
+                if outputAsset.tracks(withMediaType: AVMediaType.video).isEmpty {
+                  try? FileManager.default.removeItem(at: outputURL)
+                  onFailure(CompressionError(message: "Compression produced a file with no video track"))
+                } else {
+                  onCompletion(outputURL)
+                }
               } else {
                 onFailure(CompressionError(message: "Compression succeeded but output URL is unavailable"))
               }