如果Delphi应用程序有许多TImage组件，我怎么能保持它的大小？

Question

I want to make an application using Delphi. The problem is I am going to have a lot of TImage components in it - which will make the exe size extremely large. So far my exe is 20MB large and I have only completed the home page, by my calculations the exe alone will be more than 10GB in size - which is way too much.

How can I make an app with hundreds/thousands of images and yet let the exe be small in size?

Answer 1

Don't put the images in the executable. Keep them in external files and load them at runtime.

This will require you to stop loading the images into the TImage controls at design-time and instead use dynamic code to load the image, and transfer to the TImage control. There are many advantages of doing so:

1. You keep your executable down to a reasonable size, one that can fit in the virtual address space.
2. You can use the most appropriate compression format for the images. If I recall correctly, a Delphi TImage will persists to a .dfm file in a very inefficient way. You can choose to use PNG or JPEG compression.
3. Keeping the files external allows you to better managed them when developing. You can keep them as separate files in your revision control system. Storing images in .dfm files makes for painstaking updates when you need to change the images. You have to do lots of interaction with the IDE. Storing as files allows you to overwrite the file, and commit to the repository.

Answer 2

If you don't need to keep your images in their original size, you can read them in at program startup and scale them to their "working" size. This will reduce your memory requirements immensely - for example, reducing an image to half its original width and height reduces memory requirements to a quarter of the original image.

If the images don't change, you can do this offline in a separate build process and reduce the load time a lot too. Otherwise, you can cache the reduced images during the load process to speed it up the next time the program is started.

Answer 3

You might find the binary code includes all the images as PNG file format, so it will be compile extremely application size for you.

I use the images in runtime, as JPG, so in the form's OnCreate events you can load from the Package.

Use the "Project" Menu "Deployment" to include your JPG files to the APK.

You can read more here: http://blogs.embarcadero.com/davidi/2013/11/23/43005/