How to optimize the algorithm embedded bitmap fonts(have picture)?

Question

0.00/5 (No votes)

See more:

Embedded systems (CPU slow, limited memory) is often used dot matrix font, such as 12 * 16 dot matrix can be binary, see the linked image http://hi.csdn.net/attachment/201111/3/3652857_1320325279YaZf.jpg[^]

But this memory is memory space occupied.
How to use the appropriate algorithm to optimize, and analyse their advantages and disadvantages of the given code and the time and space complexity of algorithms?

Posted 5-Nov-11 19:15pm

PEIYANGXINQU

Updated 6-Nov-11 0:22am

André Kraak

v9

Add a Solution

Comments

Mehdi Gholam 6-Nov-11 1:54am

Your image file is forbidden, please fix it.

PEIYANGXINQU 6-Nov-11 5:01am

I have try to fix it many times ,but I can not do it. <img src="http://hi.csdn.net/attachment/201111/3/3652857_1320325279YaZf.jpg" alt="picture"/>Can you tell me how to upload a picture to this websit?Thank you!

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Accepted Answer · 2011-11-05T22:00:00

Without seeing you linked image (as Medhi says, it gives 403 - forbidden) it is difficult to be accurate, but...

It varies, depending on the application and the hardware. And to a certain extent the programmers personal preferences.

If you are talking about low resolution text, and a limited processor, then storing character fonts as direct binary can be the best method: it is reasonably compact (each character in a 12*16 array only needs 24 bytes) and it is a fixed length, so it is simple to index to the appropriate character for display. If you start to get clever with your storage, you can save space, and even store characters in an arrangement that makes life easier when you display them - but this depends heavily on your hardware, and also on your processing power - the more complex the character storage algorithm, the longer it takes to display a character, and this may be a very important criteria of an embedded system - if you miss your "slot" you will not get the chance again.

For example, I had one embedded system for printing on cardboard cartons as they moved down a production line. The print head was vertical, at 90 degrees to the movement of the boxes, and the resolution was reasonably high - 180 dpi, 128 separate dots. So my font storage was optimized for printing: each character was stored as a number of vertical lines in a vertical slice through the character - since I only had a Z80 to do the processing, and 32K of RAM in total, I had to be quick, but densly packed. As it became time to print each vertical column of the character, it was a simple case of clear the memory area, and set the appropriate black pixels. If I had stored this in a format suitable for an LCD display, then it would have been in horizontal slices by byte, and much slower to output from the print head.