custom_thumbnail_video 0.6.3

A flutter plugin for creating a thumbnail from a local video file or from a video URL.

video_thumbnail

This plugin generates thumbnail from video file or URL. It returns image in memory or writes into a file. It offers rich options to control the image format, resolution and quality. Supports iOS / Android / web.

Methods

function	parameter	description	return
thumbnailData	String [video], optional Map<String, dynamic> [headers], ImageFormat [imageFormat](JPEG/PNG/WEBP), int [maxHeight](0: for the original resolution of the video, or scaled by the source aspect ratio), [maxWidth](0: for the original resolution of the video, or scaled by the source aspect ratio), int [timeMs]generates the thumbnail from the frame around the specified millisecond, int[quality]`(0-100)	generates thumbnail from [video]	[Future<Uint8List>]
thumbnailFile	String [video], optional Map<String, dynamic> [headers], String [thumbnailPath](folder or full path where to store the thumbnail file, null to save to same folder as the video file) this ignored on the web, ImageFormat [imageFormat](JPEG/PNG/WEBP), int [maxHeight](0: for the original resolution of the video, or scaled by the source aspect ratio), int [maxWidth](0: for the original resolution of the video, or scaled by the source aspect ratio), int [timeMs] generates the thumbnail from the frame around the specified millisecond, int [quality](0-100)	creates a file of the thumbnail from the [video]	[Future<String>]

Warning:

Giving both the maxHeight and maxWidth has different result on Android platform, it actually scales the thumbnail to the specified maxHeight and maxWidth. To generate the thumbnail from a network resource, the video must be properly URL encoded.

Usage

Installing add get_thumbnail_video as a dependency in your pubspec.yaml file.

dependencies:
  get_thumbnail_video: ^0.6.1

import

import 'package:get_thumbnail_video/video_thumbnail.dart';

Generate a thumbnail in memory from video file

final uint8list = await VideoThumbnail.thumbnailData(
  video: videofile.path,
  imageFormat: ImageFormat.JPEG,
  maxWidth: 128, // specify the width of the thumbnail, let the height auto-scaled to keep the source aspect ratio
  quality: 25,
);

Generate a thumbnail file from video URL

XFile thumbnailFile = await VideoThumbnail.thumbnailFile(
  video: "https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4",
  thumbnailPath: (await getTemporaryDirectory()).path,
  imageFormat: ImageFormat.WEBP,
  maxHeight: 64, // specify the height of the thumbnail, let the width auto-scaled to keep the source aspect ratio
  quality: 75,
);

final image = kIsWeb ? Image.network(thumbnailFile.path) : Image.file(File(thumbnailFile.path));

Generate a thumbnail file from video Assets declared in pubspec.yaml

final byteData = await rootBundle.load("assets/my_video.mp4");
Directory tempDir = await getTemporaryDirectory();

File tempVideo = File("${tempDir.path}/assets/my_video.mp4")
  ..createSync(recursive: true)
  ..writeAsBytesSync(byteData.buffer.asUint8List(byteData.offsetInBytes, byteData.lengthInBytes));

final fileName = await VideoThumbnail.thumbnailFile(
  video: tempVideo.path,
  thumbnailPath: (await getTemporaryDirectory()).path,
  imageFormat: ImageFormat.PNG,  
  quality: 100,
);

Limitations on the Web platform

Flutter Thumbnail on the Web platform has some limitations that might surprise developers more familiar with mobile/desktop targets.

In no particular order:

CORS headers

This plugin requires the server hosting the video to include appropriate CORS headers in the response. Specifically, the server must include the Access-Control-Allow-Origin and Access-Control-Allow-Methods headers in the response to the request. For more information, please refer to the Mozilla Developer Network documentation.

HTTP range headers

This plugin requires the server hosting the video to support HTTP range headers. If the server does not support range requests, the plugin may generate a thumbnail from the first frame of the video instead of the desired frame. For more information, please refer to the Mozilla Developer Network documentation.

Notes

Fork or pull requests are always welcome. Currently it seems have a little performance issue while generating WebP thumbnail by using libwebp under iOS.