Is it possible to either capture the "failed to load resource" error or find a method to play local videos with satisfactory quality?

How can I tackle the failed to load resource problem when utilizing the HTML5 <video> tag for playing LAN videos served by a server? Moreover, what could be causing the frequent pauses without buffering when attempting to play videos locally using file://…/? I’m interested in potential solutions or insights from those who’ve faced similar issues.

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Yes, it is possible to capture the failed to load resource error while playing the local videos within a WKWebView or WebView on macOS. Not only that, you can also, optimize the playback quality of local videos.

This error occurs when the given video file cannot be found or loaded by the browser or web view. You can use JavaScript and the error event connected to the video> element to capture and manage such errors:

<video controls id="myVideo">
   <source src="your_video.mp4" type="video/mp4">

   const video = document.getElementById('myVideo');
   video.addEventListener('error', (event) => {
      console.error('Video loading error:',;

By including this code, the video element is connected to an event listener that responds whenever a loading error occurs. You can then record the precise error information for thorough troubleshooting.

You can enhance the playback quality by following these recommendations to ensure that local videos are played back in a manner that results in satisfactory video quality:

  • Video Compression and formats

It’s important to choose video formats that are broadly compatible with a variety of devices and browsers when choosing a video format for the web. Popular options include Ogg (which uses Theora codec), WebM (which supports VP8/VP9 codecs), and MP4 (which uses the H.264 codec). These formats are renowned for their robust compatibility and efficient compression.

Compression is necessary for lowering video file size while maintaining acceptable levels of visual quality. It’s important to use compression codecs like H.264 or VP9 that successfully balance video quality and file size. By fine-tuning compression parameters like bitrate, resolution, and frame rate, desirable results can be obtained.

  • Resolution Control

Make sure that your video’s resolution and the web view’s display dimensions are perfectly in sync. By doing this, needless scaling or ugly letterboxing are avoided, both of which can have a negative effect on the quality and user experience. It is recommended to choose resolutions like 720p (1280x720) or 1080p (1920x1080) based on the design of your website and the capability of users’ devices.

  • Buffered Bitrates

The bitrate plays a key role in deciding how much data is transferred per second when watching a video. The correct bitrate must be chosen in order to balance video quality and download times. While larger bitrates provide better quality, they may also result in slower loading times. In contrast, lower bitrates reduce quality in order to speed up loading.

Choosing variable bitrate (VBR) encoding is a decision that should be carefully thought through. VBR automatically distributes fewer bits to straightforward segments and more bits to complex situations. This strategy maintains quality during visually challenging moments while saving space during less difficult sections.

  • CControls for playback

Giving users access to a variety of playback controls, such as play, pause, volume control, and seek capability, gives them the ability to customize their viewing experience. These controls make it easier to modify the video’s quality, fine-tune the playback options, and move easily across the video’s content.

Giving users the ability to manually change the video quality is advantageous when appropriate. Users with slower internet connections can take advantage of this functionality by choosing a lower-quality option for smoother playback.

  • Optimizing preloading

Preloading can help reduce the likelihood of buffering interruptions during video viewing. Preloading includes loading a portion of the video before playing begins, which is especially important for longer videos or viewers with slow connections.

Make sure that the preloading process seamlessly blends with the user’s experience in cases where videos are set to autoplay. The goal is to make sure that as soon as the user initiates playback, the movie starts playing smoothly.

DO let me know if you have more questions on this.