eliu
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新竹, 台灣 | | 1 | subject:
RGB | 
3
0 | 2009-10-03 | quote | | |
目前的RGB 還是 24-bit，R/G/B 只有one byte，所以只能顯示 256 種灰階，只要長寬大於 > 256 的圖，灰階變化就不夠。
其實有些高階的繪圖工作站 RGB 是 48-bit的，R/G/B channel 是 16-bit，這樣就可以顯示 65536種灰階。
我們可以看到 GTK & X11 介面的 RGB 早就是 48-bit 的，只可惜不知道什麼時候我們的 RGB 才會進化成48-bit的。
| GTK & X11 | typedef struct {
guint32 pixel;
guint16 red;
guint16 green;
guint16 blue;
} GdkColor;
typedef struct {
unsigned long pixel;/∗ pixel value */
unsigned short red, green, blue;/∗ rgb values */
char flags; /∗ DoRed, DoGreen, DoBlue */
char pad;
} XColor; |
Windows 好像沒聽過有 48-bit 的RGB，只要 Windows 不動，我們就永遠停留在 24-bit RGB？
| Windows Win32 | | COLORREF RGB(
BYTE byRed,
BYTE byGreen,
BYTE byBlue
); |
當然我們需要48-bit 的顯示卡 & 顯示器monitor & 印表機printer 。另外，不知道有什麼 image file 支援 48-bit RGB，TIFF 好像有。還有，我們需要 48-bit RGB 的 digital camera，這已經有了。
edited: 11
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coolcd
joined:
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之前看過一些 photoshop 教學，會把相片轉成 16bit RGB，再去處理，得到的色彩看起來很鮮豔，可是我覺得看起來有點假，猜想可能是螢幕沒有支援 16bit 的關係。
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eliu
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新竹, 台灣 |
| coolcd | | 之前看過一些 photoshop 教學，會把相片轉成 16bit RGB |
不知道為何要這樣做。目前的 dc or dslr應該都是 24-bit 的
edited: 1
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coolcd
joined:
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posted:
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| | eliu | |
不知道為何要這樣做。目前的 dc or dslr應該都是 24-bit 的
|
記得是為了避免調整階調時斷階的問題
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ziyawu
joined:
2009-08-15
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Taiwan | | 5 | subject:
RGB |
0
0 | 2009-10-03 | quote | | |
| eliu | |
當然我們需要48-bit 的顯示卡 & 顯示器monitor & 印表機printer 。另外，不知道有什麼 image file 支援 48-bit RGB，TIFF 好像有。
|
CinePaint 支援的有 DPX、OpenEXR 和 16-bit TIFF。
(據說電影畫面編輯的最低要求是 16 位元深度)
Photoshop 的 PSD 也可以。
ziyawu on deviantART
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coolcd
joined:
2008-01-21
posted:
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google 了一下 CinePaint
原來這看似不起眼的程式這麼厲害，等我切到 Debian 也來用用看
Top Reasons to Use CinePaint
- Support for 8-bit, 16-bit and 32-bit color channels of deep
paint.
- High fidelity image file types such as DPX, OpenEXR and 16-bit
TIFF. These files can't be opened in ordinary 8-bit image applications
(e.g., GIMP) without crushing them.
- High Dynamic Range. HDR images can go brighter than white.
Ordinary images can't be brighter than a white sheet of paper
(0=black, 1.0=white).
- Gallery-quality printing. B&W photographs have only one
color channel and degrade quickly when manipulated as 8-bit images.
CinePaint has higher fidelity and offers a 16-bit printing path
to the print-head using GutenPrint.
- Color Management System. CinePaint uses LittleCMS.
- Flipbook. Movie playback of short sequences of images in
RAM.
- Innovation. CinePaint offers features that go beyond ordinary
painting tools.
- It's used to make feature films at major studios.
- Open Source. With various OSS licenses, because it uses code
from various sources, including GPL, LGPL, BSD, and MPL.
- Free.
- Friendly professional developers. Polite discussion forums.
- Being a CinePaint developer can be a good career move. CinePaint
developers have gotten jobs at companies such as DreamWorks Animation,
Sony Pictures Imageworks, and Apple.
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