import 'dart:typed_data'; import 'dart:ui'; import 'package:matrix/matrix.dart'; import 'package:native_imaging/native_imaging.dart' as native; import 'run_in_background.dart'; const int defaultMax = 800; Future resizeImage(MatrixImageFile file, {int max = defaultMax}) async { // we want to resize the image in a separate isolate, because otherwise that can // freeze up the UI a bit // we can't do width / height fetching in a separate isolate, as that may use the UI stuff // somehow doing native.init twice fixes it for linux desktop? // TODO: once native imaging is on sound null safety the errors are consistent and // then we can properly handle this instead // https://gitlab.com/famedly/company/frontend/libraries/native_imaging/-/issues/5 try { await native.init(); } catch (_) { await native.init(); } _IsolateArgs args; try { final nativeImg = native.Image(); await nativeImg.loadEncoded(file.bytes); file.width = nativeImg.width; file.height = nativeImg.height; args = _IsolateArgs( width: file.width, height: file.height, bytes: file.bytes, max: max); nativeImg.free(); } on UnsupportedError { final dartCodec = await instantiateImageCodec(file.bytes); final dartFrame = await dartCodec.getNextFrame(); file.width = dartFrame.image.width; file.height = dartFrame.image.height; final rgbaData = await dartFrame.image.toByteData(); final rgba = Uint8List.view( rgbaData.buffer, rgbaData.offsetInBytes, rgbaData.lengthInBytes); dartFrame.image.dispose(); dartCodec.dispose(); args = _IsolateArgs( width: file.width, height: file.height, bytes: rgba, max: max); } final res = await runInBackground(_isolateFunction, args); file.blurhash = res.blurhash; final thumbnail = MatrixImageFile( bytes: res.jpegBytes, name: file.name != null ? 'scaled_' + file.name.split('.').first + '.jpg' : 'thumbnail.jpg', mimeType: 'image/jpeg', width: res.width, height: res.height, blurhash: res.blurhash, ); // only return the thumbnail if the size actually decreased return thumbnail.size >= file.size || thumbnail.width >= file.width || thumbnail.height >= file.height ? file : thumbnail; } class _IsolateArgs { final int width; final int height; final Uint8List bytes; final int max; final String name; _IsolateArgs({this.width, this.height, this.bytes, this.max, this.name}); } class _IsolateResponse { final String blurhash; final Uint8List jpegBytes; final int width; final int height; _IsolateResponse({this.blurhash, this.jpegBytes, this.width, this.height}); } Future<_IsolateResponse> _isolateFunction(_IsolateArgs args) async { // Hack for desktop, see above why try { await native.init(); } catch (_) { await native.init(); } var nativeImg = native.Image(); try { await nativeImg.loadEncoded(args.bytes); } on UnsupportedError { nativeImg.loadRGBA(args.width, args.height, args.bytes); } if (args.width > args.max || args.height > args.max) { var w = args.max, h = args.max; if (args.width > args.height) { h = args.max * args.height ~/ args.width; } else { w = args.max * args.width ~/ args.height; } final scaledImg = nativeImg.resample(w, h, native.Transform.lanczos); nativeImg.free(); nativeImg = scaledImg; } final jpegBytes = await nativeImg.toJpeg(75); final blurhash = nativeImg.toBlurhash(3, 3); final ret = _IsolateResponse( blurhash: blurhash, jpegBytes: jpegBytes, width: nativeImg.width, height: nativeImg.height); nativeImg.free(); return ret; }