Bmp2g9b with 8 bits/pixel V9990

Pagina 1/4
| 2 | 3 | 4

Door Manel46

Champion (463)

afbeelding van Manel46

16-11-2018, 17:23

Hi, people
I am testing with bitmap graphics for V9990, with uncompressed bmp2g9b (-b) files.
Thus I get BD16 (16 bits / pixel), BP6 (6 bits / pixel) and BP4 (4 bits / pixel) graphics, starting from the appropriate BMPs. But I can not make graphics in BD8 mode (8 bits / pixel). If the BMP has 256 colors gives error. For this reason I have to use SR8 files, which limits me to a 256x212 pixel screen.
Is it possible to make g9b files of any size in this mode?

Aangemeld of registreer om reacties te plaatsen

Van msd

Paragon (1372)

afbeelding van msd

17-11-2018, 10:02

The problem is that the v9990 only has 8 bit 64 color mode with palette support and a 8 bit mode fixed palette like the v99x8. I never thought it was interesting to add the 8 bit 256 color mode. It would not be difficault to add this mode .

Van msd

Paragon (1372)

afbeelding van msd

17-11-2018, 10:06

It only needs to be added to bmp2g9b. The g9klib already supports it

Van Manel46

Champion (463)

afbeelding van Manel46

17-11-2018, 11:13

msd wrote:

I never thought it was interesting to add the 8 bit 256 color mode. It would not be difficault to add this mode .

Yes friend, to this I mean, the fixed palette of 256 colors, which is the BD8. It would be nice to have bmp2g9b in this mode. As I said, I have to use SR8 for these graphics, with the limitation of the screen dimension.

Van Manel46

Champion (463)

afbeelding van Manel46

17-11-2018, 12:08

msd wrote:

It only needs to be added to bmp2g9b. The g9klib already supports it

It would be something great. If, as I said, I use the 8-bit / pixel mode, 256 colors, but for 256-by-wide screens.

Van Manel46

Champion (463)

afbeelding van Manel46

18-11-2018, 16:57

Hi msd
It is very interesting that you implement the 256 color mode (8 bits / pixel) for the bmp2g9b. When you can.
I wait for news. Smile

Van Manel46

Champion (463)

afbeelding van Manel46

28-11-2018, 15:38

Seeing the possibilities of BMP2G9B, I reaffirm the need that 256 color bmp can be converted.
A die, for me of a lot of weight:
It works perfectly with 64 color bmp, but it turns out that this (6 bit / pixel) dismisses two bits in each byte, while the 256 color mode uses them all. A graphic of 64 colors occupies the same as that of 256, which is much better.
I solve the loading of a 512x424 screen, in this mode, by four SR8, which I then charge with LMMC. But it is a cumbersome process.

Van msd

Paragon (1372)

afbeelding van msd

28-11-2018, 16:47

Yes but it is 64 colors out of 32768 versus 256 out of a fixed pallet

Van msd

Paragon (1372)

afbeelding van msd

28-11-2018, 16:57

There are two possibilities
24 bit fixed palette to 8 bit fixed palette
8 bit with 24 bit palette to 8 bit fixed palette

Which one?

Van Manel46

Champion (463)

afbeelding van Manel46

28-11-2018, 17:01

If right. But the quality of the resulting image is superior. Better "dither". The BMP2MSX converter works very well for this.

Van Manel46

Champion (463)

afbeelding van Manel46

28-11-2018, 17:46

msd wrote:

There are two possibilities
24 bit fixed palette to 8 bit fixed palette
8 bit with 24 bit palette to 8 bit fixed palette

Which one?

Here there is no palette, as with the 16 bit / pixel BD16 mode
Analyzing B9G, the bitmap data is continuation of the header, in these modes. The 8-bit / pixel mode is the BD8.
Look link.

http://msxbanzai.tni.nl/v9990/manual.html

Pagina 1/4
| 2 | 3 | 4