invalid ADLER32 while drawing image about lv_lib_png

[kisvegabor]

Maybe the image is slightly corrupted and full featured desktop viewers can handle it.

I suggest opening and saving the image. Hopefully it'll fixes it.

[glory-man]

Maybe the image is slightly corrupted and full featured desktop viewers can handle it.

I suggest opening and saving the image. Hopefully it'll fixes it.

I thought about it, but unfortunaly not helped. I was able to draw image by disabling adler32 checking.

[glory-man]

By the way errors 57 & 58 description tells that - (checking CRC can be disabled) / (checking ADLER32 can be disabled). So in lodepng.h may be added code like this

#ifdef LV_PNG_IGNORE_ADLER32
#define LODEPNG_IGNORE_ADLER32 1
#else
#define LODEPNG_IGNORE_ADLER32 0
#endif

#ifdef LV_PNG_IGNORE_CRC
#define LODEPNG_IGNORE_CRC 1
#else
#define LODEPNG_IGNORE_CRC 0
#endif

So in decompress initialization function may be used LODEPNG_IGNORE_CRC/LODEPNG_IGNORE_ADLER32 instead of 0/1. In this case we don't need edit sources to configure library.

[kisvegabor]

I've just downloaded the image form your first post and it worked for me.

lodepng was update a couple of month ago. Do you use the latest version from the master branch?

[glory-man]

I've just downloaded the image form your first post and it worked for me.

lodepng was update a couple of month ago. Do you use the latest version from the master branch?

I use lvgl_v7 as part of zephyr os. I made zephyr-module lv_lib_png based on commit 7ff6168.
As far as I understand later commits mades for lvgl_v8 which is incompatible with lvgl_v7

[kisvegabor]

What if you overwrite lodepng.c/h with the latest versions? There shouldn't be v8 related stuff there.

It might also worth a try to download the image from your post. Maybe GitHub converted it.

[glory-man]

What if you overwrite lodepng.c/h with the latest versions? There shouldn't be v8 related stuff there.

It might also worth a try to download the image from your post. Maybe GitHub converted it.

I'll try it. Thanks.

[glory-man]

What if you overwrite lodepng.c/h with the latest versions? There shouldn't be v8 related stuff there.

It might also worth a try to download the image from your post. Maybe GitHub converted it.

I tried latest version of lodepng.c. This file uses
lv_fs_seek(&f, 0, SEEK_END)
with 3 params (inside lodepng_filesize), while in lvgl_v7 it has only 2 params. So I use
lv_fs_size(&f, &size);
to detect size of file.
But file still not opened without disabling adler32 checking.

[kisvegabor]

And have you downloaded the image from GitHub (from your first comment)?

[glory-man]

And have you downloaded the image from GitHub (from your first comment)?

Yes. I tried with image downloaded from github.
In debugger
unsigned ADLER32 = lodepng_read32bitInt(&in[insize - 4]);
called in lodepng_zlib_decompressv function gives me 0xC0C64FFD, while
unsigned checksum = adler32(out->data, (unsigned)(out->size));
gives 0xBF592DC8, out->size = 0x230

[kisvegabor]

I have no idea 🙁

I've tested it again and out->size = 0x230 for me too but checksum = 0xc0c64ffd.

[glory-man]

I have no idea 🙁

I've tested it again and out->size = 0x230 for me too but checksum = 0xc0c64ffd.

I founded a problem. I use custom allocator function, where lodepng_realloc was incorrect. Fixed by using lv_mem_realloc.

[kisvegabor]

Glad to hear that!