REM（快速眼动）睡眠是大多数梦境发生和记忆巩固的时期。对认知功能和情绪调节至关重要。
照片滤镜
关于此工具
为您的照片应用Instagram风格的滤镜和调整，然后下载结果。
使用方法
- 1 上传任意照片，即时应用一键预设滤镜，或使用滑块精细调整亮度、对比度、饱和度、模糊和色调。并排的前后对比视图让您实时比较变化。对结果满意后，使用Canvas像素处理将编辑后的图片下载为PNG。
- 2 第1步：点击上传区域或拖放图片文件上传照片。
- 3 第2步：点击任意预设滤镜（如复古、戏剧性、棕褐色）进行一键变换。
- 4 第3步：使用调整滑块精细调整亮度、对比度、饱和度、模糊和色调。
How these filters work
This tool adjusts a photo using the same five image operations browsers expose through the CSS filter property: brightness, contrast, saturation, blur, and hue-rotate (plus an invert toggle inside some presets). While you drag the sliders, the change is applied live to the preview by setting a CSS filter — fast and non-destructive, because it only restyles how the image is displayed. When you click Download PNG, the tool re-renders the photo onto an HTML canvas with the exact same filter "baked in" and exports a real PNG, so the file you save looks like the preview.
Everything happens on your device. Your image is read locally as a data URL and never uploaded — which means private photos stay private and the tool works even with no internet connection.
What each control actually does
| Control | Range | Effect |
|---|---|---|
| Brightness | 0–200% (100 = original) | Below 100 darkens; above 100 lightens the whole image |
| Contrast | 0–200% | Pushes tones toward black and white; high values look punchy, low values flat |
| Saturation | 0–200% | 0% is grayscale; above 100% intensifies color |
| Blur | 0–10px | Softens detail; useful for backgrounds or a dreamy look |
| Hue Rotate | 0–360° | Shifts every color around the color wheel by the given angle |
The key mental model is that 100% means "leave it alone" for brightness, contrast, and saturation. Sliding below 100 reduces the effect; above 100 amplifies it. Blur and hue start at 0, meaning no change.
The presets, and how they are built
The preset buttons are just saved combinations of those same sliders, so you can start from a look and then fine-tune. For example, Grayscale sets saturation to 0%. Sepia warms the image with a small hue shift and reduced saturation. Dramatic pushes contrast to 180% while dropping brightness slightly for a bold, moody result. Vivid raises saturation to 180% for punchy color, while Faded lowers contrast and lifts brightness for a soft, washed look. Selecting a preset moves the sliders to its values; nudging any slider afterward switches the label to "Custom" so you know you have departed from the preset.
A worked example
Upload a slightly dull outdoor photo. Click Vivid to jump to high saturation and contrast, then notice the greens and blues snap to life. If it now looks too intense, drag saturation back from 180% toward 130%. The sky still looks gray? Add a small hue rotation — try 200° to push neutrals cooler — and lift brightness to 105%. When the preview matches what you want, click Download PNG. The canvas applies brightness(105%) contrast(115%) saturate(130%) blur(0px) hue-rotate(200deg) to the full-resolution image and saves it as filtered-photo.png. Because the export uses the original image dimensions, you do not lose resolution.
Practical tips
- Edit in small steps. Big contrast or saturation jumps clip detail. Move 10–15 points at a time and watch the before/after panels side by side.
- Fix exposure before color. Get brightness and contrast right first, then adjust saturation and hue. Correcting color on a too-dark image fights against itself.
- Use blur sparingly. Even 1–2px noticeably softens a photo. It is great for a subtle glow but quickly destroys sharpness on detailed images.
- Hue-rotate creatively, not for white balance. Hue rotation spins all colors together, so it is a stylistic effect, not a true white-balance correction. Use it for posters and moods, not for neutralizing a color cast precisely.
- Reset is your friend. The Reset button returns every slider to 100/0 so you can start a new look from the original without re-uploading.
Common mistakes
- Exporting before previewing fully. The PNG matches the preview at download time. Make sure the After panel shows exactly what you want before clicking Download.
- Expecting a smaller file. The export is always PNG at full resolution, which is lossless but can be larger than the original JPG. Use it when quality matters; compress separately if you need a small file.
- Pushing saturation to 200% on portraits. Skin tones go orange fast. Portraits usually look best with saturation near 100–120%.
- Treating blur as background-only. The filter blurs the entire image, not just the background. There is no subject selection here; it is a whole-image effect.
Because the photo is processed entirely in your browser, this is a safe way to retouch personal or sensitive images — nothing is sent to a server, and the edited PNG is generated on your own machine.