Fix image upload bottleneck - #1039
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Initialize `MimeTypeResolver` statically once instead of re-instantiating it on every `lookupType` call. Simplify `lookupType` to directly pass `headerBytes` to `_resolver.lookup`, ensuring magic numbers are evaluated first regardless of whether the file path has an extension. Expose `magicNumbersMaxLength` getter to allow memory-safe, partial file stream reads when determining MIME types.
… and memory-safe fallbacks Integrate flutter_image_compress for hardware-accelerated image processing on Android, iOS, and macOS, drastically reducing execution time. Refactor image processing and MIME resolution pipeline: - Add `_resolveMimeType` to read header magic numbers via partial file streams without allocating full payloads in RAM. - Use `img.decodeImageFile` in pure-Dart `_fallbackProcessImage` isolate to stream directly from disk for Windows/Linux. - Guard `processFile()` to resolve missing MIME types upfront and prevent `LateInitializationError` on unsupported attachments. - Update Android `ndkVersion` in build config to resolve native C++ compilation warnings and plugin toolchain mismatches.
Guard against uninitialized video controllers, add try/catch for platform exceptions on corrupt files, and provide a fallback MIME type for video thumbnails.
K-Zawis
marked this pull request as draft
August 31, 2026 17:48
…mes on linux as well
K-Zawis
marked this pull request as ready for review
August 31, 2026 18:26
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Description
This PR addresses a major performance bottleneck during file uploads where pure-Dart decoding caused multi-second UI freezes and high memory allocation that has been plaguing me during my use of Commet (as I mainly use it on mobile). It also patches several fatal crash vectors (
NullCheckError,LateInitializationError, and platform exceptions) in both the image and video processing pipelines.Key Changes
flutter_image_compressto utilize hardware-accelerated media pipelines on Android, iOS, and macOS._fallbackProcessImage) forLinux andWindows that streams image bytes directly from disk (img.decodeImageFile) instead of allocating full payloads in RAM, avoiding OOM spikes.processVideo()against uninitialized controllers/corrupted media, and replaced force-unwrap operators (!) in the image pipeline with safe null checks to prevent unhandledNullCheckErrors on unsupported file types._resolveMimeTypeto read header magic numbers via partial file streams, safely resolving missing MIME types upfront and preventingLateInitializationErrors.ndkVersionto28.2.13676358to resolve native C++ plugin toolchain mismatches.Performance Benchmarks
Tested on a physical Samsung Galaxy S22 Ultra (SM-S908B) processing a standard 12 MP photo (5.41 MB, 3000×4000 resolution):
package:image):4,754 msflutter_image_compress):289 ms(Note: Native C-codec execution via
flutter_image_compress_linuxwas also verified on Linux x86_64, providing a noticeably snappier frame response compared to pure-Dart isolate decoding.)