OK, so I'll assume everyone has seen the posts by our host @Like Ra asking for the file size of pictures and, I shall assume, videos to be reduced.
I have had a quick check of my recent posts and my own images seem to vary in size between 100-300Kb - which was a relief as I know their 'raw' size can be anything up to 40Mb!
My tactic for doing this was simple, just send the image from my mobile device (which is what I normally use to take the photos) by email to another of my accounts - this always prompts me to 'reduce image size', which I do and voila!
But can I reduce them further? I've tried a number of approaches (cropping, editing, screen shoots, etc) with limited success at getting the file sizes much under 200Kb.
So, does anyone have tips and ideas so that we can all help limit or even reduce the storage size for this forum?
18 Jan 2025, 12:36 (This post was last modified: 19 Jan 2025, 19:03 by Max515.)
My advice is this:
1) Don't use resolutions bigger than necessary.
- For a product example picture = 200-300px horizontal res. is enough.
- Nice, but simple photo = 800 px on longest side is enough
- Nice complex photo = 1200 px max
- A photo with lots of stuff that viewers may want to zoom-in on, such as the pics with all the objects used in a bondage session = use the best resolution that you have.
- When taking pictures, know that the background counts! A simple, uniform background is more compressible than having lots and lots of objects in the background.
2) Don't more colors than necessary
- If an image is black text and graphics on white background (or reverse), or if shades of gray aren't really needed = reduce it to black-and-white before saving. This allows CCITT compression (see below).
- No colors (or not important) = reduce it to grayscale
- Simple graphics with few colors and exact colors match isn't that important = reduce it to 4 / 8 / 16 / 256-color. Don't use dithering if possible; it badly affects compression ratios.
3) Use appropriate file format and compression
- Black and white (not grayscale) images, especially the ones without dithering = use TIFF with CCITT group 4 compression. This is by far the best format for B/W. A page of text (A4/Letter) scanned B/W at 300 dpi and saved in this format will be around 50KB. It's lossless too!
- Screen captures with a very limited number of colors, no gradients, no photos on the background, just simple text and simple graphics = use PNG, with no transparency. It's also lossless! My screenshot below is 7KB.
- Grayscale complex images, grayscale photos = use grayscale JPEG
- Color complex images, photos = use normal JPEG
- Complex images where you don't want any quality loss = use TIFF with LZW compression
- Short animations with simple graphics and low resolution (!) = use GIF (this is the only good use for this image format)
- Any animations more complex or long = use a video format instead
BTW, TIFF can have multiple pages, just like a PDF. And if you ever want to save to PDF, know that it too can use lossless LZW for color and CCITT for B/W as internal image formats.
For image processing I recommend IrfanView. It's only downside is that it doesn't support webp (yet).
It has an option to set file size when saving in JPEG format. See screenshot below. It will adjust image quality to fit that size. But I don't recommend using it! Forcing an image to a specific file size results in very bad image quality for complex images and wasted bytes for simple pics. Just use the quality slider instead. 80-85 is a good choice most of the time.
IrfanView can also do batch processing of entire folders of images.
FastStone Image Viewer is another powerful viewer which also offers batch processing, so you can quickly convert, resize and rename a bunch of images. Like IrfanView, the UI is not the most modern, but it's versatile, quick and does its job.
As for image editing, I have been using the Affinity Products from Serif Software for a while now.
Not free, but very reasonable one-time payment purchases, available for Windows, MacOS and Ipad.
Affinity Photo standalone costs around $/EUR 80, but it's often discounted to 40-50% off.
They also offer their full "universal" suite (Photo, Designer, Publisher) for $/EUR 180, which also gets discounted regularly.
The universal suite contains licences for all three apps on all three platforms (so you can use it on your Windows PC and your iPad for instance).
No Linux versions though.
I bought the standalone Photo v1 app five years ago for EUR 25 and upgraded to the fuil 2.0 universal suite for another ~ EUR 68.
Life's too short to pretend you're not into some kinky shit.
