Video Compression Artifacts Explained—and How to Fix Them with AI

What Are Video Compression Artifacts?

Video compression artifacts are visual imperfections that show up when a video has been heavily compressed. Instead of a clean, smooth image, you might see blocky patterns, strange color bands, or fuzzy edges. These flaws aren’t part of the original footage—they’re side effects of the way video data is reduced to save space.

To understand why this happens, it helps to know a bit about how video compression works. Most videos are compressed using “lossy” methods, which means some image information is permanently discarded to make the file smaller. The idea is to remove data that’s less noticeable to the human eye—but when the compression goes too far, those missing details start to show.

In short, compression artifacts are the visible scars left behind by over-compression. They’re especially common in low-bitrate videos, re-encoded files, or clips that have been shared and uploaded multiple times.

Common Types of Video Compression Artifacts

Compression artifacts don’t all look the same—they come in different forms depending on how the video was compressed and how much quality was lost. Here are some of the most common types you’ve probably seen before, with examples to help you recognize them.

1. Blocking – When the Video Turns into a Grid

You’ve probably seen this one before. You're watching a video, maybe a landscape or a cloudy sky, and suddenly the image breaks into little squares—almost like someone overlaid a checkerboard on it. This is what’s known as blocking.

It tends to show up when a video has been compressed too much. Most video encoders chop the image into small chunks (called macroblocks), and if there’s not enough data to fill in each chunk properly, you end up with visible seams between them. It’s especially obvious in low-detail areas—like skies, shadows, or walls—and gets worse during fast motion or panning shots.

The result? Instead of smooth gradients or soft textures, you’re stuck looking at digital bricks. It’s one of the clearest signs that a video has been compressed past its breaking point.

2. Color Banding – The Death of Smooth Gradients

Have you ever seen a sunset in a video that looked like it was made of five big stripes of color instead of one smooth transition from orange to blue? That’s color banding.

This artifact happens when compression reduces the number of available colors or shades in a gradient. Instead of a smooth fade, the image “jumps” between color levels, creating harsh lines or rings. Banding is particularly noticeable in scenes with soft lighting, smoke, fog, or shadows—anywhere that subtle shifts in tone are key to the mood.

It doesn’t ruin the video, but it does flatten the visual experience. It’s like replacing a watercolored sky with one drawn in crayons.

3. Blurring – When Details Just Vanish

You know that disappointing moment when a video looks sharp in the thumbnail but turns out soft and smeary when you hit play? That’s compression blur in action.

To reduce file size, encoders often sacrifice fine details—textures like skin, hair, grass, text, or fabric patterns. Instead of crisp outlines, you get vague shapes. Faces lose character, backgrounds lose depth, and everything starts to look a bit like it was filmed through a layer of Vaseline.

You’ll see this a lot on platforms that auto-compress uploads, like messaging apps or social media. And while blur might not be as glaring as blocking or banding, it quietly chips away at image quality, making everything feel low-res—even when the resolution says otherwise.

4. Mosquito Noise – The Flickering Swarm Around Edges

This one’s trickier to spot, but once you see it, you can’t unsee it. Look around the sharp edges of text, logos, or faces in a compressed video, and you might notice tiny dots or flickers buzzing around the borders. That’s mosquito noise.

It happens because the video encoder struggles to cleanly preserve edges during motion or high contrast. Instead of a crisp boundary, you get noisy interference that looks like static dancing around outlines. It’s named “mosquito noise” because of how it swarms and flickers unpredictably, especially during movement.

You’ll often spot it near subtitles, news tickers, or anything with hard edges against a plain background. It’s subtle, but it can be incredibly distracting—like having a swarm of insects hover just outside your vision.

5. Color Bleeding – When Colors Leak Across the Lines

Sometimes, it looks like the colors in your video can’t stay in their lanes. Red lipstick smears beyond the lips. A bright logo spills into the surrounding background. This is called color bleeding.

The root cause? Compression simplifies color data separately from brightness. When there’s too much reduction, the boundaries between colors become less precise, and high-saturation areas (like reds and blues) begin to “bleed” into adjacent zones. It’s especially visible in footage with bold text, graphics, or facial features.

Color bleeding doesn’t just look messy—it can distort important details. In product videos, it can misrepresent branding; in tutorials or interviews, it can distract from the message.

Can You Fix Video Compression Artifacts?

The short answer? Yes—but it depends on the severity of the artifacts and the tools you use.

Once video compression artifacts appear, they’re not always easy to remove because some original data has already been lost during compression. Unlike a simple glitch that can be fixed by re-rendering the file, artifacts are baked into the video’s pixels. However, modern technology has made it possible to significantly reduce or even eliminate many common artifacts, improving video quality after the fact.

How to Reduce Compression Artifacts

1. Use Higher Bitrate or Less Compression When Encoding

The best way to avoid artifacts is to prevent them in the first place. When exporting or saving videos, try using higher bitrates or codecs that balance compression with quality. This reduces the chances of visible artifacts appearing. However, this isn’t always practical for streaming or sharing where smaller file sizes are needed.

2. Apply Noise Reduction and Sharpening Filters

Video editing software often includes filters to smooth out blocky areas, reduce color banding, or sharpen blurry edges. While these filters can help, they often require careful tuning and may not fully restore the original detail.

3. Upscale and Enhance with AI-Powered Tools

This is where AI video enhancers come into play. Advanced AI-based software like Aiarty Video Enhancer can analyze video frames and intelligently reconstruct lost details, reduce noise, and fix color distortions. These tools don’t just apply generic filters—they learn patterns from millions of images to restore natural textures and edges, often with impressive results.

How to Use Aiarty Video Enhancer to Fix Video Compression Artifacts

Fixing video compression artifacts has never been easier thanks to Aiarty Video Enhancer’s intuitive interface and powerful AI algorithms. Here’s a quick step-by-step guide to help you remove blocking, blurring, color banding, and other compression flaws from your videos:

Step 1: Download and Install Aiarty Video Enhancer

First, click the button below to download and install Aiarty Video Enhancer on your computer. The software supports Windows and macOS and comes with a free trial so you can test its capabilities before committing.

Step 2: Launch the Program and Import Your Video

Open Aiarty Video Enhancer and click the “+” button or drag and drop your compressed video file into the main window. Aiarty supports a wide range of formats, so you won’t need to worry about compatibility issues.

Step 3: Choose the AI Model

Pick the AI model based on the types of compression artifacts in your video and the scene conditions:

1. moDetail-HQ v2: Best for fixing blocking and blurring in videos with lots of fine details like hair, foliage, or textured surfaces. Ideal for outdoor daylight scenes, nature footage, and portraits where preserving sharp textures and intricate details matters.
2. Smooth-HQ v2: Great for general artifact removal such as mild color banding, slight blurring, and moderate noise. It maintains smooth color gradients and natural textures, making it perfect for indoor scenes, videos with people, or footage with subtle imperfections.
3. superVideo vHQ: Designed specifically for heavy noise and mosquito noise in extremely low-light or dark scenes like night skies or dim interiors. It delivers top-notch denoising quality, though it processes more slowly, so choose this when noise reduction is your highest priority.

Step 4: Select Output Resolution and Settings

If you'd like to upscale your video (for example, from 1080p to 4K), Aiarty lets you do so while enhancing quality. Simply open the Upscale drop-down menu and choose your target resolution.

For more control, expand the Export Settings panel to customize the output format, codec, and destination folder.

Step 5: Preview the Results

Before exporting the full video, click the Preview button to generate preview.

Once the inference is complete, you’ll be able to compare the original and enhanced frames side by side to see how well compression artifacts have been removed.

In this example, Aiarty’s artifact removal works impressively well. The “Before” frame shows noticeable blocking artifacts, especially in flat areas, while the “After” frame appears smooth and clean, with the blockiness completely eliminated.

Step 6: Start the Enhancement Process

If you're satisfied with the preview, click Add Task, then hit Export Current to begin processing. Aiarty’s AI engine will automatically analyze each frame, remove compression artifacts, restore lost detail, and enhance overall visual quality.

Now just sit back and let Aiarty do the work. Processing time may vary depending on your hardware and settings.

Final Thoughts

Compression artifacts are visual flaws that show up when a video is overly compressed. Whether it’s blocking, color banding, blurring, mosquito noise, or color bleeding, these artifacts can degrade the viewing experience and reduce professional quality.

Most of them occur during uploading, downloading, or real-time streaming, where video data is compressed to save space or bandwidth. Social media platforms, messaging apps, or online editors often apply aggressive compression automatically.

The best way to avoid compression artifacts is to use higher bitrates, choose better codecs, and avoid multiple rounds of exporting or re-sharing. But what if the damage is already done?

That’s where tools like Aiarty Video Enhancer come in. Instead of trying to mask flaws with basic filters, Aiarty uses advanced AI to analyze each frame, restore lost detail, clean up noise, and bring back natural textures and sharpness.

Give it a try and take control of your video quality.