Ostatnio aktywny 1 month ago

How to create high quality gr-paint images.

Ron Economos zrewidował ten Gist 9 years ago. Przejdź do rewizji

1 file changed, 7 insertions, 1 deletion

gr-paint.md

@@ -73,4 +73,10 @@ A quick tutorial on how to get high quality images from gr-paint and Gqrx.
73 73
74 74 ![High Contrast Example](http://www.w6rz.net/paintbowie.png)
75 75
76 - ![High Contrast Example](http://www.w6rz.net/paintqpsk.png)
76 + ![High Contrast Example](http://www.w6rz.net/paintqpsk.png)
77 +
78 + ![High Contrast Example](http://www.w6rz.net/paintstarfire.png)
79 +
80 + ![High Contrast Example](http://www.w6rz.net/paintnrol39.png)
81 +
82 + ![High Contrast Example](http://www.w6rz.net/witchbladep.png)

Ron Economos zrewidował ten Gist 10 years ago. Przejdź do rewizji

1 file changed, 2 insertions

gr-paint.md

@@ -18,6 +18,8 @@ A quick tutorial on how to get high quality images from gr-paint and Gqrx.
18 18
19 19 ![Calibration Example](http://www.w6rz.net/paintcal.png)
20 20
21 + ![Calibration Example](http://www.w6rz.net/paintpanda.png)
22 +
21 23 ## Black and white waterfall hack
22 24
23 25 * In the file gqrx/src/qtgui/plotter.cpp, make the following change.

Ron Economos zrewidował ten Gist 10 years ago. Przejdź do rewizji

1 file changed, 5 insertions, 1 deletion

gr-paint.md

@@ -67,4 +67,8 @@ A quick tutorial on how to get high quality images from gr-paint and Gqrx.
67 67
68 68 * High contrast images work best, especially drawings.
69 69
70 - ![High Contrast Example](http://www.w6rz.net/paintliz11.png)
70 + ![High Contrast Example](http://www.w6rz.net/paintliz11.png)
71 +
72 + ![High Contrast Example](http://www.w6rz.net/paintbowie.png)
73 +
74 + ![High Contrast Example](http://www.w6rz.net/paintqpsk.png)

Ron Economos zrewidował ten Gist 10 years ago. Przejdź do rewizji

1 file changed, 70 insertions

gr-paint.md(stworzono plik)

@@ -0,0 +1,70 @@
1 + # High Quality Spectrum Painting
2 +
3 + A quick tutorial on how to get high quality images from gr-paint and Gqrx.
4 +
5 + ![Spectrum Example](http://www.w6rz.net/paintpalvin.png)
6 +
7 + ## Setup
8 +
9 + * Use a newer version of Gqrx with Ref. level and dB range sliders.
10 + * Set the FFT size in Gqrx to 32768
11 + * Set the waterfall rate to 50 or 60 fps
12 +
13 +
14 + ## Calibration
15 +
16 + * Transmit the supplied ramp.bin file.
17 + * Adjust the Ref. level and dB range sliders so that the test pattern lowest level bar is at black or near black and the highest level bar is at bright yellow.
18 +
19 + ![Calibration Example](http://www.w6rz.net/paintcal.png)
20 +
21 + ## Black and white waterfall hack
22 +
23 + * In the file gqrx/src/qtgui/plotter.cpp, make the following change.
24 +
25 + ```
26 + // default waterfall color scheme
27 + #if 0
28 + for (int i = 0; i < 256; i++)
29 + {
30 + // level 0: black background
31 + if (i < 20)
32 + m_ColorTbl[i].setRgb(0, 0, 0);
33 + // level 1: black -> blue
34 + else if ((i >= 20) && (i < 70))
35 + m_ColorTbl[i].setRgb(0, 0, 140*(i-20)/50);
36 + // level 2: blue -> light-blue / greenish
37 + else if ((i >= 70) && (i < 100))
38 + m_ColorTbl[i].setRgb(60*(i-70)/30, 125*(i-70)/30, 115*(i-70)/30 + 140);
39 + // level 3: light blue -> yellow
40 + else if ((i >= 100) && (i < 150))
41 + m_ColorTbl[i].setRgb(195*(i-100)/50 + 60, 130*(i-100)/50 + 125, 255-(255*(i-100)/50));
42 + // level 4: yellow -> red
43 + else if ((i >= 150) && (i < 250))
44 + m_ColorTbl[i].setRgb(255, 255-255*(i-150)/100, 0);
45 + // level 5: red -> white
46 + else if (i >= 250)
47 + m_ColorTbl[i].setRgb(255, 255*(i-250)/5, 255*(i-250)/5);
48 + }
49 + #else
50 + for (int i = 0; i < 256; i++)
51 + {
52 + if (i < 64)
53 + {
54 + m_ColorTbl[i].setRgb(i*4, i*4, i*4);
55 + }
56 + else
57 + {
58 + m_ColorTbl[i].setRgb(255, 255, 255);
59 + }
60 + }
61 + #endif
62 + ```
63 +
64 + * Note that the levels will be compressed, so the waterfall will need to be re-calibrated.
65 +
66 + ![Calibration Example Black and white](http://www.w6rz.net/paintcalbw.png)
67 +
68 + * High contrast images work best, especially drawings.
69 +
70 + ![High Contrast Example](http://www.w6rz.net/paintliz11.png)
Nowsze Starsze