example: i need to reduce the width of an image from lets say 1024 to 800. height value stays unchange.
BUT I dont want that all pixels are treated the same way.
pixels which are on the left shall basically stay untouched and the more they are located towards the right side the more squishing shall take place. almost like a perspective transform, but like i said... hight should stay the same.
No easy way to do this with your standard version of Photoshop. There might be some plug-in that could do this for you, but I'm not sure.
You could do it by hand by dividing your picture into seperate vertical lines and making all the lines into separate images. Then use the adjust image size option on the seperate lines and after you're done put them back together. The more lines you make, the smoother it will look. Here's a quick example:
You could try my method using more lines. I only used 4 and already it looks pretty good. Admittedly the procedure is better suited for some pictures than others, but I think it should work for most if you just use enough lines. Maybe you should try something around 20 lines? In my example I used 100%, 80%, 60% and 40% image width respectively on the lines. The decrease in percentage is quite large. It should look better if you take smaller steps at a time.