Ico File Extension Issues

behreandtjeremy · January 11, 2025, 8:51am

Hello,

I tried out Pro Motion NG’s .ico file format and ran into problems with the result. I’m using version 8.0.10 on Windows 10.

forIcoTest10x

This is a png of a test image 9x7 with a 10x upscale.

As far as I know, ico files follow similar restrictions as cur and ani files – they’re supposed to be powers of 2. Pro Motion NG doesn’t notify that there’s a problem with irregular sizes. And, it’s a bit easier to see the problem when the size is irregular. Sometimes a properly sized file would appear correctly in one graphics program but not load in another.

asItAppearsInGimp

This is what the icon looks like when imported into GIMP (the two alternating gray pixels are from the background checker, the pixels are transparent). Aseprite opens an empty image with all clear black pixels. Irfanview shows a decode error. XnViewMP opens a result similar to GIMP.

Row	00	01	02	03	04	05	06	07	08	09	0A	0B	0C	0D	0E	0F
00000000	00	00	01	00	01	00	09	07	00	00	01	00	20	00	F8	01
00000010	00	00	16	00	00	00	28	00	00	00	09	00	00	00	0E	00
00000020	00	00	01	00	20	00	00	00	00	00	00	00	00	00	00	00
00000030	00	00	00	00	00	00	00	00	00	00	00	00	00	00	00	FD
00000040	FF	FF	16	DB	96	FF	2F	B5	37	FF	5B	95	00	FF	88	78
00000050	00	FF	A1	49	29	FF	92	24	49	FF	82	0B	71	FF	82	0B
00000060	71	FF	00	00	00	00	00	00	01	00	00	00	00	00	00	DD
00000070	FF	FF	03	F8	E9	FF	1D	D2	7B	FF	32	AC	14	FF	62	8C
00000080	00	FF	98	6D	00	FF	FF	FF	FF	00	91	1E	53	FF	82	0B
00000090	71	FF	00	00	00	00	00	00	01	00	00	00	00	00	00	BE
000000A0	FF	FF	00	E7	FF	FF	09	EE	CE	FF	25	C8	66	FF	41	A4
000000B0	00	FF	FF	FF	FF	00	FF	FF	FF	00	FF	FF	FF	00	91	1E
000000C0	53	FF	00	00	00	00	00	00	01	00	00	00	00	00	00	A1
000000D0	FF	FF	00	C8	FF	FF	FF	FF	FF	00	10	E5	B2	FF	2B	BF
000000E0	4F	FF	50	9D	00	FF	FF	FF	FF	00	A4	53	1D	FF	92	24
000000F0	49	FF	00	00	00	00	00	00	01	00	00	00	00	00	00	7C
00000100	FF	FF	FF	FF	FF	00	FF	FF	FF	00	FF	FF	FF	00	16	DB
00000110	96	FF	2F	B5	37	FF	5B	95	00	FF	88	78	00	FF	A1	49
00000120	29	FF	00	00	00	00	00	00	01	00	00	00	00	00	00	53
00000130	FF	FF	00	88	FF	FF	FF	FF	FF	00	00	DD	FF	FF	03	F8
00000140	E9	FF	1D	D2	7B	FF	32	AC	14	FF	62	8C	00	FF	98	6D
00000150	00	FF	00	00	00	00	00	00	01	00	00	00	00	00	00	00
00000160	FF	FF	00	62	FF	FF	00	95	FF	FF	00	BE	FF	FF	00	E7
00000170	FF	FF	09	EE	CE	FF	25	C8	66	FF	41	A4	00	FF	62	8C
00000180	00	FF	00	00	00	00	00	00	01	00	00	00	00	00	00	00
00000190	FF	FF	02	00	FF	FF	07	00	FF	FF	22	00	FF	FF	70	00
000001A0	FF	FF	20	00	FF	FF	00	00	FF	FF

This is a hex dump of the file from Pro Motion NG.

icoWidth: 9 (0x09)
icoHeight: 7 (0x07)
numColors: 0 (0x00)
reserved: 0 (0x00)
icoPlanes: 1 (0x0001)
icoBpp: 32 (0x0020)
dataSize: 504 (0x000001f8)
dataOffset: 22 (0x00000016)

bmpHeaderSize: 40 (0x00000028)
bmpWidth: 9 (0x00000009)
bmpHeight2: 14 (0x0000000e)
bmpPlanes: 1 (0x0001)
bmpBpp: 32 (0x0020)
bmpCompress: 0 (0x00000000)
bmpChunk: 0 (0x00000000)

I noticed in the diagnostic printout that the data size was 504.The file only has 426 bytes.

Row	00	01	02	03	04	05	06	07	08	09	0A	0B	0C	0D	0E	0F
00000000	00	00	01	00	01	00	09	07	00	00	01	00	20	00	40	01
00000010	00	00	16	00	00	00	28	00	00	00	09	00	00	00	0E	00
00000020	00	00	01	00	20	00	00	00	00	00	00	00	00	00	00	00
00000030	00	00	00	00	00	00	00	00	00	00	00	00	00	00	00	FD
00000040	FF	FF	16	DB	96	FF	2F	B5	37	FF	5B	95	00	FF	88	78
00000050	00	FF	A1	49	29	FF	92	24	49	FF	82	0B	71	FF	55	00
00000060	AA	FF	00	DD	FF	FF	03	F8	E9	FF	1D	D2	7B	FF	32	AC
00000070	14	FF	62	8C	00	FF	98	6D	00	FF	00	00	00	00	91	1E
00000080	53	FF	7A	08	81	FF	00	BE	FF	FF	00	E7	FF	FF	09	EE
00000090	CE	FF	25	C8	66	FF	41	A4	00	FF	00	00	00	00	00	00
000000A0	00	00	00	00	00	00	8D	18	5C	FF	00	A1	FF	FF	00	C8
000000B0	FF	FF	00	00	00	00	10	E5	B2	FF	2B	BF	4F	FF	50	9D
000000C0	00	FF	00	00	00	00	A4	53	1D	FF	92	2A	3D	FF	00	7C
000000D0	FF	FF	00	00	00	00	00	00	00	00	00	00	00	00	16	DB
000000E0	96	FF	2F	B5	37	FF	5B	95	00	FF	88	78	00	FF	A1	49
000000F0	29	FF	00	53	FF	FF	00	88	FF	FF	00	00	00	00	00	DD
00000100	FF	FF	03	F8	E9	FF	1D	D2	7B	FF	32	AC	14	FF	62	8C
00000110	00	FF	98	6D	00	FF	00	00	FF	FF	00	62	FF	FF	00	95
00000120	FF	FF	00	BE	FF	FF	00	E7	FF	FF	09	EE	CE	FF	25	C8
00000130	66	FF	41	A4	00	FF	68	83	00	FF	00	00	00	00	02	00
00000140	00	00	07	00	00	00	22	00	00	00	70	00	00	00	20	00
00000150	00	00	00	00	00	00

This is hex dump for a 32bpp ico exported from GIMP. The data size listed is 320. The file size is 342 bytes.

Thanks for your time,
Jeremy

jan.cosmigo · January 12, 2025, 4:24pm

Hi @behreandtjeremy

thanks for the report. I just played around a bit, and yes, the programs don’t seem to load such files, but please see here:

Thus, a single icon file could store images of any size from 1×1 pixel up to 256×256 pixels (including non-square sizes)

The Windows file explorer displays the files correctly.

But, you are right that there is no warning if width or height exceeds 256 pixels. I should include a corresponding warning.

-Jan

P.S.: With Windows ANI files (animated cursors) there is such a warning, btw.

behreandtjeremy · January 12, 2025, 4:57pm

I think you misunderstand a secondary comment, which is a side point, not the main bug. The files are not properly formatted, regardless of their size. The example file I posted is 9x7. Irregular size just makes the problem easier to see.

jan.cosmigo · January 14, 2025, 9:15am

Hi @behreandtjeremy,

indeed, I got it wrong and was too sloppy with reading all the details
It only happens when you have a project with alpha transparency enabled. I fixed this for upcoming 8.0.11.

-Jan