NelsonChung's blog: 2007/9/30

2007年10月5日星期五

Joost 網路電視 P2P 技術

今天看到BillyPan大大分享的文章
http://www.wretch.cc/blog/billypan101&article_id=11714187
發現
已經有 Joost beta 1.0版可以下載了
不過蠻可惜的喔只有winodws版可以下載

什麼時候有Linux版可以出來呢
可以研究一下如何支援

還有Web2.0版
DNAStrem.tv 也是該大大的文章

公司有proxy 無法看 ><

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2007年10月4日星期四

截圖軟體 -scrot using in ubuntu

需要額外安裝包含
not authenticated
gliblib1
. .
libungif4g

是一個command line的方式截圖軟體
照該網頁說明
http://www.debian.org.hk/blog-entry/scrot
該功能有截全桌面部份內容降低品質॥等功能

man scrot說明文件偏向簡單化
看來是個可以練習在 Linux 上寫寫UI的好機會
or 加入一些快捷鍵
可以像windows 一樣
按Alt+PrtSc 就可以擷取最上層的視窗

man scrot

scrot(1) scrot(1)

NAME
scrot - Screen capture using imlib2

SYNOPSIS
scrot [options] [file]

DESCRIPTION
scrot is a screen capture utility using the imlib2 library to aquire
and save images. scrot has a few options, detailed below. Specify
[file] as the filename to save the screenshot to. If [file] is not
specified, a date-stamped file will be dropped in the current direc-
tory.

OPTIONS
-h, --help
display help output and exit.

-v, --version
output version information and exit.

-b, --border
When selecting a window, grab wm border too

-c, --count
Display a countdown when used with delay.

-d, --delay NUM
Wait NUM seconds before taking a shot.

-e, --exec APP
Exec APP on the saved image.

-q, --quality NUM
Image quality (1-100) high value means high size, low compression.
Default: 75. (Effect differs depending on file format chosen).

-m, --multidisp
For multiple heads, grab shot from each and join them together.

-s, --select
Interactively select a window or rectangle with the mouse.

-t, --thumb NUM
generate thumbnail too. NUM is the percentage of the original size
for the thumbnail to be.

SPECIAL STRINGS
Both the --exec and filename parameters can take format specifiers that
are expanded by scrot when encountered. There are two types of format
specifier. Characters preceded by a '%' are interpretted by strf-
time(2). See man strftime for examples. These options may be used to
refer to the current date and time. The second kind are internal to
scrot and are prefixed by '$' The following specifiers are recognised:
$f image path/filename (ignored when used in the filename)
$n image name (ignored when used in the filename)
$s image size (bytes) (ignored when used in the filename)
$p image pixel size
$w image width
$h image height
$t image format
$$ prints a literal '$'
\n prints a newline (ignored when used in the filename)

EXAMPLE
scrot '%Y-%m-%d_$wx$h.png' -e 'mv $f ~/shots/'
This would create a file called something like 2000-10-30_2560x1024.png
and move it to your shots directory.

BUGS
None known.

LICENSE
Copyright Tom Gilbert 2000

Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Soft-
ware"), to deal in the Software without restriction, including without
limitation the rights to use, copy, modify, merge, publish, distribute,
sublicense, and/or sell copies of the Software, and to permit persons
to whom the Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be included
in all copies of the Software, its documentation and marketing & pub-
licity materials, and acknowledgment shall be given in the documenta-
tion, materials and software packages that this Software was used.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MER-
CHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.

Email bugs and feature requests to

Oct 26, 2000 scrot(1)

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2007年10月1日星期一

撰寫一個中斷的sample 在embedded

首先
搞懂interrupt應該如何實做的概念
四個步驟

1. 設定GPIO為External Interrupt (引起中斷的動作)
ex. 拿 power button 當作外部中斷
先看 power button 接到哪個GPIO
通常一個GPIO是用2bits來表示四種功能
在 S3C2440 spec.中
GPF
明確定義
00 = input
01 = ouput
10 = EINT[0] (external interrupt)
11 ＝目前保留中
將power button所對應的GPIO(ex GPF0) 先設定為EINT

2.Enable interrupt (中斷啟動)
看系統 power button所對應的是哪一個中斷
如果對應到 EINT0
就設定INTMSK[0] 設定為 0 {0代表service available}
請見spec. 14-12
SRCPND and INTPND 請都將 EINT0的部份設定成1

3. 設定啟動條件
take EXTINT0 as sample
000: Low level
001: High level
01x:Falling edge triggered
10x:Rising edge triggered
11x:Both edge triggered

S3C2440a spec. p9-27
這個部份的設定會影響整體效能

4. Setting Interrupt vector
將中斷後要執行內容的位置
設定到中斷向量表中 (ISR_EINT0 位置)

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用Multi-ICE 觀看變數

CodeWorrior
編輯release版

想要用搭配 multi-ice 觀看系統變數時
會出現 "Variable removed by compiler (optimization)"

這時候
想要觀看你所宣告的變數
請到 language settings -> ARM C compiler or ARM C++ compiler (取決於你所撰寫的語言)
-> Optimizaion Level
Check Optimization level from Most( good debug view, good code) to Minimum (best debug view)