ST STM32CubeF4, User Manual

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7.3 STemWin features resources
7.3.1 JPEG decoder
The JPEG decompression uses approximately 33 Kbytes of RAM for decompression
independently of the image size and a size dependent amount of bytes. The RAM
requirement can be calculated as follows:
Approximate RAM requirement = X-Size of image * 80 bytes + 33 Kbytes
The memory required for the decompression is allocated dynamically by the STemWin
memory management system. After drawing the JPEG image the complete RAM will be
released.
7.3.2 GUI components
The operation area of STemWin varies widely, depending primarily on the application and
features used. In the following sections, memory requirements of various modules are
listed, as well as the memory requirements of example applications.
Table 13 shows the memory requirements of the main components of STemWin. These
values depend a lot on the compiler options, the compiler version and the used CPU. Note
that the listed values are the requirements of the basic functions of each module.
Camera 2467 213
(1)
62629
File Browser 3062 516 69083
Game 4188 1916 33432
Image Browser 5308 1956
(1)
32862
System 2486 89 33506
USB Device 540 29 195529
Video Player 6476 989
(1)
32646
1. The memory is allocated dynamically in some structures of this file.
Table 11. Modules footprint (continued)
File code [byte] data [byte] const [byte]
Table 12. RAM requirements for some JPEG resolutions
Resolutiont RAM usage [kbyte] RAM usage, size dependent [kbyte]
160x120 45.5 12.5
320x340 58.0 25.0
480x272 70.5 37.5
640x480 83.0 50.0