Hi, I found an issue in OSD rendering when used black color for text/date/time. Please see the images below. How to fix it? [1000056818] [1000056819] If anyone has solution for this problem, please help me. Thanks, Yugandhar

Hi @yugandhar , Can you try this patch? libispfeature.zip (377.1 KB) We will be updating on GitHub as well.

Hi @yugandhar if you are using 1bpp, [image] You can change the text color by modifying OSD_TEXT_FONT_CH_COLOR in font structure. The available colours can be found in hal_osd_avdef.h . OSD_TEXT_FONT_CH_COLOR is defined in osd_api.h .

Hi @Pammy , The issue is with black color, when used it the displayed OSD is not readable. Your suggestion is for How to change OSD color dynamically? Have you verified OSD rendering with RGB_Black and getting reproted issue?

Hi @yugandhar May I know how you set the text color to black? I’d like to follow the same steps to reproduce the result on my end. When I apply RGB_Black, my output looks like this: (Tried on isp_osd_example default example) [vlcsnap-2025-11-24-16h30m57s076]

Hi @Pammy , I am calling rts_osd_update_info(rts_osd2_type_text, &osd_text); after osd_text.font.ch_color = RGB_Black; After this call, I am seeing the text as black rectangle blocks as provided in screenshots.

Hi @yugandhar , I tried your methods on the date text. [image] I also generated a new font using, Font: SimSun Style: Regular Size: 16 custom_font_1bpp.zip (5.7 KB) and this is the result i have gotten, [vlcsnap-2025-11-25-14h23m04s623] You can use the font I generated and test again. If …

Hi @Pammy , Finally I found the root cause of OSD black color issue. The issue is due to block_alpha value in font settings. Alpha values from 0 to 3 and 12 to 15 with black color has reported issue. See the below captured images with black and red color. [black_alpha] [red_alpha] Actually I u…

Hi @Pammy , Thanks for the update. It is working now. Could you please update on below issues also. [image] Ameba Pro2 Font & Bitmap Tool Link / Documentation SDK Hi @yugandhar , The clipping happens after the PNGs are converted into the ARGB4444 font table a…

Hi @yugandhar , Yes we are looking into the issue. We will update accordingly. Thank you.

OSD text with black color showing black rectangles instead of characters

FreeRTOS Multimedia

yugandhar May 13, 2026, 10:30am 8

Hi @Pammy ,

It looks like this issue not yet resolved, can you update me on this.

Thanks,

Yugandhar

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OSD text with black color showing black rectangles instead of characters

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