From 7fe60435bce6595a9c58a9bfd8244d74b5320e96 Mon Sep 17 00:00:00 2001 From: Benjamin Franzke Date: Tue, 15 Jan 2013 08:46:13 +0100 Subject: Import DirectFB141_2k11R3_beta5 --- Source/DirectFB/docs/README.screenshots | 58 +++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100755 Source/DirectFB/docs/README.screenshots (limited to 'Source/DirectFB/docs/README.screenshots') diff --git a/Source/DirectFB/docs/README.screenshots b/Source/DirectFB/docs/README.screenshots new file mode 100755 index 0000000..7df9595 --- /dev/null +++ b/Source/DirectFB/docs/README.screenshots @@ -0,0 +1,58 @@ +How to make DirectFB screenshots +-------------------------------- + +There are two ways to generate DirectFB screenshots. The easy way is +to set the "screenshot-dir" parameter in the DirectFB configuration +file directfbrc or to pass it as a command-line option. See the +directfbrc man-page for more details. You can then generate screen +dumps in the PPM format by pressing the PrintScreen key. The PPM +files can easily be converted to others formats using for example the +netpbm tools. + +The hard way to do screenshots is to read directly from the frame +buffer device. This works for all applications that use the frame +buffer device, not only for DirectFB applications. + +The resulting data is then converted to a more convenient format using +the netpbm graphics conversion tools. If the frame buffer is not +running at 24 bit depth, the data has to be propagated to 24bit RGB +before netpbm can handle it. The tools directory contains the source +for two small utilities that do just this: + + raw16toraw24 is a small tool that reads 16bit RGB565 data from stdin, + converts to 24bit RGB888 data and writes it to stdout. + + raw15toraw24 is a small tool that reads 15bit RGB555 data from stdin, + converts to 24bit RGB888 data and writes it to stdout. + + raw32toraw24 is a small tool that reads 32bit ARGB data from stdin, + converts to 24bit RGB888 data and writes it to stdout. + + +The following steps have to be performed to take screenshots: + +Step 1 - Log in from another computer using ssh or telnet. Start your + application and stop it by pressing Ctrl+C in the remote + terminal. + +Step 2 - Read data from /dev/fb0 and write it to a file. + + examples: + [15bit] raw15toraw24 < /dev/fb0 > raw24.tmp + [16bit] raw16toraw24 < /dev/fb0 > raw24.tmp + [24bit] cat /dev/fb0 > raw24.tmp + [32bit] raw32toraw24 < /dev/fb0 > raw24.tmp + +Step 2 - Convert data to ppm using rawtoppm and specify the resolution of + the frame buffer. + + example: rawtoppm 800 600 raw24.tmp > ppm24.tmp + +Step 3 - Convert ppm to png using pnmtopng. + + example : pnmtopng screenshot.png + + +Thats it! + + -- cgit