Improve Jpeg Image Quality

JPEGs (also called JPGs) are images that have been compressed to create smaller files - perfect for sharing or posting online. As a result, when you attempt to enlarge or re-use a JPEG, the image may appear grainy or pixelated. You can enhance the quality of your JPEG files by fine-tuning the image’s appearance, color, and contrast with a photo editor. If you're relatively comfortable with image manipulation, Topaz DeJPEG may be a great add-on to your current software; if you're just starting out you may want to try free software like Pixlr. If you're already familiar with Photoshop, access the powerful tools there to improve your image file!

Steps

Using Pixlr

  1. Download or launch Pixlr online. Pixlr is a powerful photo-editing tool used by professionals and photo-editing enthusiasts. Pixlr offers a free online editor as well as a basic editing app for desktop and mobile. You may also upgrade to a more advanced version of the product with a regular subscription.
    • Pixlr is the company’s desktop application. You can download a free trial from https://pixlr.com/desktop. The full version costs $1.99/month or $14.99/year.
    • Pixlr Editor is the company’s web-based application. Go here to launch Pixlr editor: https://pixlr.com/editor/
    • Pixlr Express is the company’s web, iOS, and Android application.You can download it for free from the Google Play or Apple App store, or by going to https://pixlr.com/express/.[1]
  2. Open the image you want to edit. The quality of your final, edited product is dependent upon the resolution, or pixel count, of the original image. Pixlr strongly encourages its users to start every editing project with the highest resolution version of the image possible. This is especially true if you intend to blow-up the photo—as you increase the size of a low resolution image, the white space between pixels increases, causing the picture to appear distorted.[2] To upload a picture with:
    • Pixlr, select File > Open and choose the picture from your library or database. Mac users may use the shortcut ⌘ Command+O; Windows users may use the shortcut Ctrl+O.
    • Pixlr Editor, click on the “Browse” button, select the JPEG file, click “Ok” or find an image on the web by clicking the “Open URL” button.[3]
    • Pixlr Express, click on the “photos” button and choose an image from your phone or tablet’s library. You may also capture a new image to edit by clicking on the “camera” button.
  3. Resize the image. A file’s size is determined by its pixel count—the higher the pixel count, the larger the file. Emailing, uploading, and downloading large JPEGs is a slow process. Resizing your image to a smaller pixel count will allow you to share your pictures faster.
    • To resize the picture using Pixlr, select Fast > Resize. Set the pixel dimensions to the desired size, keep the “Aspect Ratio” locked, and click “Apply.”
    • To resize the picture using Pixlr Editor, select Adjustment > Resize. Change the pixel dimensions to the desired size, keep the “Aspect Ratio” locked, and click “Apply.”
    • To resize the image with Pixlr Express, click “Done” and then select “Resize.” Alter the pixel dimensions to the desired size, keep the “Aspect Ratio” locked, and click “Apply.”[4]
  4. Crop the image. Cropping allows you to easily remove unwanted portions of a photo. Cropping an image will also reduce the file’s size.
    • To crop your image using Pixlr, select Fast > Crop. Manually alter the dimensions of the bounding box or enter in the pixel dimensions. Click “Apply.”
    • To crop your image using Pixlr Editor, select Adjustment > Crop. Manually alter the width and length of the bounding box. Click outside of the picture. If you are happy with the new dimensions, click “Yes” in the dialog box that appears.
    • To crop your picture using Pixlr Express, select Tools > Crop. Key in the desired pixel dimensions or select one of the pre-set size options from the drop down menu.[4]
  5. Reduce the image’s noise. This filter is only available for free with Pixlr Editor or with a subscription to Pixlr. Select Filter > Denoise. The word “Denoise” will flash above the photo, indicating the the image’s noise, or visual distortion, was reduced. Continue to reduce the noise until you achieve the desired results.
    • You can not control how much noise is reduced at one time.[5]
  6. Use the paintbrush tool to reduce noise. The paintbrush tool is only available for free through Pixlr Editor or with a subscription to Pixlr. You can reduce the appearance of pixelation by painting over the discolored pixels. Reserve the paintbrush tool to correct areas that do not have a lot of fine detail.
    • Zoom in until you can see the individual pixels clearly. Select View > Zoom In.
    • Select the eyedropper tool from the toolbox—it is located directly above the hand icon. Use the eyedropper to select a color near the block you would like to paint over.
    • Select the paintbrush tool—it is located directly above the paint can icon. Click on the number next to the word “Brush” to expand the tool’s settings. Reduce the brush’s opacity to 40% and set the brush’s hardness to 10%. Select a brush shape and diameter that suits your needs.
    • Carefully “dab” the paintbrush over the pixels to blend the colors together. Use single clicks to apply the paint to the image. Use the eyedropper tool to change the color as needed.
    • To reduce the mosquito noise, or distortion that occurs along edges of objects, you will need to apply colors from the object and its surroundings. Reducing the brush’s size and opacity will provide you with more control over the application.
    • Periodically zoom in and out to assess your work.
  7. Retouch areas of fine detail with the clone stamp tool. This feature is only available for free through Pixlr Editor or with a subscription to Pixlr. Pixlr’s clone stamp tool allows you to capture and replicate portions of an image. With this tool, you can copy and paste individual pixels or entire objects. Since the stamp can capture and replicate multiple colors, this tool is wonderful for eliminating or reducing mosquito noise from areas with fine details.
    • Zoom in until you can see the individual pixels. Select View > Zoom In.
    • In pixlr, the stamp is applied with a brush. Select the brush tool and adjust its settings. Choose a soft edge brush from row two and reduce the opacity. The soft edges and low opacity will allow you to blend the colors together.
    • Select the clone stamp tool—it is located directly below the paint can icon. Move your cursor to the exact location you would like to capture and replicate. To activate the clone stamp, windows users must hold down Alt and Mac users must hold down ⌘ Command. As you hold down the key, click on the area. Release the key and mouse.
    • To apply the stamp, move your cursor to the area you would like to touch up and click. Repeat as needed.
    • Throughout the process, zoom in and out to examine your work.[6]
  8. Refine the image’s color and contrast. Pixlr provides users ways to alter and enhance an image. You may use the “Color” tool to adjust the image’s hue, saturation, lightness and vibrance. If the image is over or underexposed, you can alter the pictures contrast or brightness with the “Contrast” tool.[7]
    • To access these tools in Pixlr, select Refine > Color or Refine > Contrast.
    • To access these tools in Pixlr Editor, select Adjustment > Color or Adjustment > Contrast.
    • To access these tools in Pixlr Express, select Tools > Adjustment > Color or Tools > Adjustment > Contrast.
  9. Fine tune the image with various tools. Pixlr is equipped with multiple brush-like tools and filters that are capable of erasing minor flaws or altering the entire picture. These tools include:
    • Sharpen: use this tool to sharpen soft edges
    • Blur: use this tool to soften harsh edges
    • Smudge: use this tool to blend pixels together
    • Sponge: use this tool to “soak up” color or “saturate” color
    • Dodge: use this tool to increase the image’s brightness
    • Burn: use this tool to add shadow, or contrast, to your picture
    • Spot Heal: use this tool to remove blemishes and scratches
    • Bloat: use this tool to create a concave effect
    • Pinch: use this tool to produce a convex effect
    • Red Eye Reduction: use this tool to remove red eyes[8]
  10. Apply an effect to the image. With Pixlr’s effects package, you can transform each pixel in your image. Every effect tool uses math to alter the appearance of individual pixels. Pixlr offers nine different effects. Each effect has several sub-effect options. The categories include:
    • Atomic, Creative, Default, Soft, Subtle, Too Old, Unicolor, and Vintage.[9]
  11. Save the image and adjust its quality size. Once you have finished editing your image, select File > Save As, click the “Save” button, or pick “Save Image.” If you are using Pixlr or Pixlr Editor, a dialog box will appear on the screen. In Pixlr, you will have the option to rename the image, choose the “Files of Type”—choose JPEG— and determine where you would like to save the image. Once you are done, click “Save.” In Pixlr Editor, you will have the option to rename the file. Before the image is saved, the program will prompt you to select the “Image Quality.”
    • High-quality images are less compressed—the pixels retain more data. This results in a large file and a crisp picture.
    • Low-quality images are more compressed—the pixels contain less data. This creates a small file size and a less crisp, or more pixelated, picture.[9]

Using Topaz DeJPEG

  1. Verify that Topaz DeJPEG works with your photo editing software.[10] Topaz DeJPEG is a JPEG-improving plugin for your primary photo editing software. The free trial version of the plugin can be used with Adobe Photoshop (Windows and Mac), Paintshop Pro (Windows), Photo Impact (Windows), and Irfanview (Windows).
  2. Download and install the plugin.[11] To download the free trial version, visit www.topazlabs.com/download in your web browser. Enter your e-mail address and choose an account password, then click “Download Now.” Scroll down to “Topaz DeJPEG” and choose your operating system (Windows or Mac). The download will begin, and your trial license key will be sent to you via email.
    • Close Photoshop. If you use Adobe Photoshop, you’ll need to close it before running the DeJPEG installer. This step is not necessary for users of other programs.
    • Run the installer. Double-click the downloaded installer file to start the trial. Enter the trial license key (sent to your email) when prompted, then click “Install” to begin the installation.
  3. Import DeJPEG into your photo-editing software. Before you can use the plugin, you’ll need to add the DeJPEG filter folder to your program. The full path to the DeJPEG plugin folder is Program Files >> Topaz Labs >> Topaz DeJPEG 4.
    • Photoshop: Photoshop users can skip to the next step, as DeJPEG automatically installs to the Photoshop plugins folder.
    • Paintshop Pro: In the File menu, select “Preferences,” then “File Locations.” Choose “Plugins” on the left side of the screen, then click the “Add” button. Navigate to the DeJPEG plugin folder, then click “OK.”
    • Photo Impact: Open the program and press F6 on the keyboard. Choose “Plugins” from the list, then click the “…” button at the end of the first empty plugin folder on the list. In the folder list, select the DeJPEG plugin folder, then click “OK.” Restart Photo Impact before attempting to use the filter for the first time.
    • IrfanView: Open the program, then expand the “Image” menu. Click “Effects,” then “Adobe 8BF Filters.” Choose “Add 8BF filters” from the menu. Now, navigate to the DeJPEG plugin folder, then click OK.
  4. Launch the filter. Open your JPEG in your typical photo-editing software, then launch the DeJPEG tool:
    • Photoshop: In the Filters menu, choose “Topaz Labs,” then “DeJPEG 4.”
    • Paintshop Pro: In the Effects menu, choose “Plugins,” then select “Topaz DeJPEG.”
    • Photo Impact: Open the Effect menu, then select “Topaz DeJPEG.”
    • IrfanView: Open the Image menu, click “Effects,” then “Adobe 8BF Filters.” Choose “Topaz DeJPEG” from the filter list.
  5. Zoom in on a problem area. Click the magnifying glass (+) to zoom in to a portion of your image where compression artifacts are apparent.
  6. Cycle through the default presets. The DeJPEG default presets are located on the left side of the screen. Click each default preset to have its settings applied to the preview of your image. Notice how each preset improves or disrupts the quality of the image. Choose the preset that best perfects your JPEG image. It’s okay if it’s not perfect, there are still more settings to tweak.
  7. Adjust the sliders in Luminance mode. Select “Luminance” from the options beneath “Preview Display mode.” Now click “Main” to view several options to fix the details left out by the preset.
    • Reduce Artifacts: First, move the slider all the way to the left. Now, gradually move the slider the right while examining the detail in the preview pane. As you move the slider to the right, the edges may soften, but noise and checkerboarding will disappear. Keep moving to the right until you’ve found a pleasing balance.
    • Sharpen: This slider should help redefine the edges softened by the Reduce Artifacts slider. As you move this slider to the right, the sharpness will increase.
    • Sharp Radius: This slider should be used in conjunction with Sharpen tool. Experiment by moving this slider to the left and right until the edges look clear and the artifacts are gone.
  8. Adjust color details. If the colors in your image seem to have been affected by the previous tools, switch to Color mode by selecting "Color" under Preview Display Mode.
    • Smooth Color: Move this slider to the right and left until you are satisfied with the image in the preview pane.
    • Clear Edge Radius. If you want to adjust the detail of the colors at the edges, click to the "Advanced" settings, then raise "Clr Edge Radius" slider. Use this tool with the Edge Threshold slider until you’re happy with the image.
    • Adjust Saturation. If the colors appear weak, move the "Saturation" slider to the right to increase color levels.
    • Add grain. Try using the "Add Grain" slider to make the image appear more natural. Move the slider to the right to increase the amount of grain.
  9. Zoom out to view your changes. Before saving your work, click the magnifying glass (-) until you can see the entirety of the image in the preview pane. If you don’t like the results, continue working with the presets, luminance and color settings until you’re satisfied with the entire photo.
  10. Click “OK” to process the image. You may need to wait a few moments for the filter to apply.

Using Adobe Photoshop

  1. Consider what quality you actually need the image to be. Fixing the fine details of a low-quality, compressed JPEG takes quite a bit of time and dedication.
    • If you’re pressed for time or don’t have Photoshop, see the Topaz DeJPEG method.
    • If you want to improve images for use in apps like Facebook or Instagram, this method won’t be as helpful as using an app with filters. Pixlr contains free filters that can disguise imperfect JPEGs. If you want to make your photos pop and don’t care about compression loss, give Pixlr a try.
  2. Zoom in for a closer look. Open your JPEG in Photoshop, then zoom in by clicking the magnifying glass (+) at the top left of the toolbar. Continue clicking this button until the percentage at the bottom left corner of the screen says “300%.” Notice the blocks and compression discolorations that appear at this close level.
  3. Locate the “Reduce Noise” filter. Open the “Filter” menu, select “Noise,” then “Reduce Noise.”
  4. Adjust noise reduction options.[12] First, place a check in the box that says “Preview” so you can see your changes in real time.
    • Strength: This number will reflect the desired degree of noise removal; it should be higher for JPEGs of lesser quality. Drag the slider to the right to see the effect of raising the strength setting.
    • Preserve Details: A lower percentage will make the picture blurrier and softer, but will also reduce more noise.
    • Sharpen Details: You may want to compensate for a low Preserve Details setting with a higher Sharpen Details setting, as that will make the edges of your image clearer. Make sure "Remove JPEG artifact" is checked.
    • Once you’re satisfied with the preview image, click “OK” to save the new image.
  5. Minimize mosquito noise and colorblocking in large areas without much fine detail. (E.g., human skin, cheeks, hair.) Your goal is to make the different color transitions in the image to be as smooth as possible. Leave important details in specific objects (e.g., eyes, ears) for the rubber stamp/clone tool, which will be covered shortly.
    • Zoom into the image until you can clearly see the colorblocks (tiny colored squares) in the area you're working with.
    • Use the eyedropper tool to select a color near the colorblocks that you'd like to remove.
    • Select the brush tool. You will essentially be lightly painting over the colorblocks. Set the brush hardness to 10%, opacity to 40%, and flow to 100%.
    • Using one-clicks, "dab" the paint brush over the colorblocks. Don't hold the cursor down and paint--it will appear unnatural. Feel free to switch colors liberally to accurately match the colors, shadows, and highlights of the original picture.
    • Lower the brush opacity to 10% for smoothing over transition areas, such as where the eyebrow meets the skin. You'll want to pick colors from both the skin and the eyebrow to dab over this transitional space. Because of the low opacity, any changes that you make will be incremental and thus appear natural, so don't be afraid of dabbing skin color on the eyebrow edge and vice versa.
  6. Use the rubber stamp/clone stamp tool in areas with great fine detail.[13] (E.g., eyes, teeth, insect wings.) Because it's hard to pick one color that would be appropriate for dabbing with a brush in these areas, we can compensate for that by using the rubber stamp to get an exact match of colors. The rubber stamp allows you to select an area of the image that you can literally stamp and replicate elsewhere on the image.
    • Click the rubber/clone stamp while pressing the Alt key until the cursor turns into a crosshair. Select an area immediately next to a color block or other compression artifact, but avoid the colorblock. You wouldn't want to stamp any compression artifacts.
    • Set the brush size to what's appropriate for dealing with the compression artifact -- you probably want to stay between 1 and 10 px. Set the "hardness" to a value between 10 and 30% and "opacity" to 30%. Use the same one-click "dabs" to fix blocks that are the wrong color. Frequently re-select the area you would like to be stamped (by holding down the alt key) as you move across the image.
    • Reduce the opacity for transitional areas. Incorrect blocks of color sometimes interfere with the shape of the image (note where parts of the iris are not a smooth round shape but rather interrupted by protruding lines). You may have to use dabs to essentially re-draw edges damaged by incorrect colorblocks.
  7. Repeat your use of these tools until you are satisfied with the results. Periodically zoom out to 100% to view results across your entire image.
  8. Save the image as a high quality JPEG or a PNG, which supports more colors. You don't want your efforts to be wasted with another round of compression.
    • In Photoshop, go to File >> Save for Web & Devices.
    • In the drop-down menu, select "JPEG" and set the quality to a value between 80 and 100. Note that higher quality entails a larger file size.
    • Alternatively, select "PNG-24" to save your file as a PNG. PNGs typically are larger than JPEGs, but they do not heavily compress images.


Tips

  • Photoshop's history only saves a certain number of past clicks, and you will be making lots of clicks to fix your image up. You might zoom-out and realize a huge flaw that was made more clicks ago than Photoshop saved. To prevent this from happening, frequently take snapshots of your image, so you can always go back to those stages of your image if you don't like a change you made. The snapshot button can be found on the bottom of the history panel. Scroll all the way up in the same panel to see all of your snapshots.
  • Don't be afraid to play around with brush and rubber stamp settings, especially as you get more experienced with Photoshop. If you don't like the way a dab affected your image, change the settings.
  • If you're working with a photograph, pay attention to the different colors present. A blue flower may have shades of blue, navy, green, purple, tan, etc. depending on the lighting, shadows, and reflections. Try your best to incorporate these colors as much as possible with a low-opacity brush tool. Consider switching to the rubber stamp tool if there is an overwhelming number of different colors in a small space.

Related Articles

Sources and Citations

  1. ↑ https://support.pixlr.com/hc/en-us/articles/210066517-What-are-the-differences-between-Pixlr-apps-
  2. ↑ https://support.pixlr.com/hc/en-us/articles/209350208-A-quick-primer-on-image-resolution-DPI-and-professional-printers-
  3. ↑ https://pixlr.com/express/
  4. ↑ 4.0 4.1 http://www.microscope-microscope.org/imaging/image-resolution.htm
  5. ↑ http://www.gcflearnfree.org/imageediting101/4.5
  6. ↑ https://support.pixlr.com/hc/en-us/articles/209350178-How-to-use-the-clone-stamp-tool-in-Pixlr-Editor
  7. ↑ https://intra.wps60.org/webcentral/images/stories/Documents/PIXLRImageEditor.pdf
  8. ↑ https://support.pixlr.com/hc/en-us/articles/210066477-The-Pixlr-Editor-toolbar-explained?flash_digest=c75743f88fa5c3028c791027dd4b3262b6fd39be
  9. ↑ 9.0 9.1 http://www.glaciergateway.org/UserFiles/Servers/Server_1143719/File/pdf/Pixlr.pdf
  10. ↑ http://www.topazlabs.com/dejpeg_static/UsersGuide.pdf
  11. ↑ https://support.topazlabs.com/hc/en-us/articles/200255213-Download-and-Installation-Instructions
  12. ↑ http://www.photoshopessentials.com/photo-editing/reduce-noise/
  13. ↑ http://digital-photography-school.com/12-tips-for-mastering-the-clone-stamp-tool-in-photoshop/
Retrieved from "https://kipkis.com/index.php?title=Improve_Jpeg_Image_Quality&oldid=356396"