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1da177e4 LT |
1 | Frequently Asked Questions: |
2 | =========================== | |
3 | subject: unified zoran driver (zr360x7, zoran, buz, dc10(+), dc30(+), lml33) | |
4 | website: http://mjpeg.sourceforge.net/driver-zoran/ | |
5 | ||
6 | 1. What cards are supported | |
7 | 1.1 What the TV decoder can do an what not | |
8 | 1.2 What the TV encoder can do an what not | |
9 | 2. How do I get this damn thing to work | |
10 | 3. What mainboard should I use (or why doesn't my card work) | |
11 | 4. Programming interface | |
12 | 5. Applications | |
13 | 6. Concerning buffer sizes, quality, output size etc. | |
14 | 7. It hangs/crashes/fails/whatevers! Help! | |
15 | 8. Maintainers/Contacting | |
16 | 9. License | |
17 | ||
18 | =========================== | |
19 | ||
20 | 1. What cards are supported | |
21 | ||
22 | Iomega Buz, Linux Media Labs LML33/LML33R10, Pinnacle/Miro | |
23 | DC10/DC10+/DC30/DC30+ and related boards (available under various names). | |
24 | ||
25 | Iomega Buz: | |
26 | * Zoran zr36067 PCI controller | |
27 | * Zoran zr36060 MJPEG codec | |
28 | * Philips saa7111 TV decoder | |
29 | * Philips saa7185 TV encoder | |
30 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
31 | videocodec, saa7111, saa7185, zr36060, zr36067 | |
32 | Inputs/outputs: Composite and S-video | |
33 | Norms: PAL, SECAM (720x576 @ 25 fps), NTSC (720x480 @ 29.97 fps) | |
34 | Card number: 7 | |
35 | ||
36 | Linux Media Labs LML33: | |
37 | * Zoran zr36067 PCI controller | |
38 | * Zoran zr36060 MJPEG codec | |
39 | * Brooktree bt819 TV decoder | |
40 | * Brooktree bt856 TV encoder | |
41 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
42 | videocodec, bt819, bt856, zr36060, zr36067 | |
43 | Inputs/outputs: Composite and S-video | |
44 | Norms: PAL (720x576 @ 25 fps), NTSC (720x480 @ 29.97 fps) | |
45 | Card number: 5 | |
46 | ||
47 | Linux Media Labs LML33R10: | |
48 | * Zoran zr36067 PCI controller | |
49 | * Zoran zr36060 MJPEG codec | |
50 | * Philips saa7114 TV decoder | |
51 | * Analog Devices adv7170 TV encoder | |
52 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
53 | videocodec, saa7114, adv7170, zr36060, zr36067 | |
54 | Inputs/outputs: Composite and S-video | |
55 | Norms: PAL (720x576 @ 25 fps), NTSC (720x480 @ 29.97 fps) | |
56 | Card number: 6 | |
57 | ||
58 | Pinnacle/Miro DC10(new): | |
59 | * Zoran zr36057 PCI controller | |
60 | * Zoran zr36060 MJPEG codec | |
61 | * Philips saa7110a TV decoder | |
62 | * Analog Devices adv7176 TV encoder | |
63 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
64 | videocodec, saa7110, adv7175, zr36060, zr36067 | |
65 | Inputs/outputs: Composite, S-video and Internal | |
66 | Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps) | |
67 | Card number: 1 | |
68 | ||
69 | Pinnacle/Miro DC10+: | |
70 | * Zoran zr36067 PCI controller | |
71 | * Zoran zr36060 MJPEG codec | |
72 | * Philips saa7110a TV decoder | |
73 | * Analog Devices adv7176 TV encoder | |
74 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
75 | videocodec, sa7110, adv7175, zr36060, zr36067 | |
76 | Inputs/outputs: Composite, S-video and Internal | |
77 | Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps) | |
78 | Card number: 2 | |
79 | ||
80 | Pinnacle/Miro DC10(old): * | |
81 | * Zoran zr36057 PCI controller | |
82 | * Zoran zr36050 MJPEG codec | |
83 | * Zoran zr36016 Video Front End or Fuji md0211 Video Front End (clone?) | |
84 | * Micronas vpx3220a TV decoder | |
85 | * mse3000 TV encoder or Analog Devices adv7176 TV encoder * | |
86 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
87 | videocodec, vpx3220, mse3000/adv7175, zr36050, zr36016, zr36067 | |
88 | Inputs/outputs: Composite, S-video and Internal | |
89 | Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps) | |
90 | Card number: 0 | |
91 | ||
92 | Pinnacle/Miro DC30: * | |
93 | * Zoran zr36057 PCI controller | |
94 | * Zoran zr36050 MJPEG codec | |
95 | * Zoran zr36016 Video Front End | |
96 | * Micronas vpx3225d/vpx3220a/vpx3216b TV decoder | |
97 | * Analog Devices adv7176 TV encoder | |
98 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
99 | videocodec, vpx3220/vpx3224, adv7175, zr36050, zr36016, zr36067 | |
100 | Inputs/outputs: Composite, S-video and Internal | |
101 | Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps) | |
102 | Card number: 3 | |
103 | ||
104 | Pinnacle/Miro DC30+: * | |
105 | * Zoran zr36067 PCI controller | |
106 | * Zoran zr36050 MJPEG codec | |
107 | * Zoran zr36016 Video Front End | |
108 | * Micronas vpx3225d/vpx3220a/vpx3216b TV decoder | |
109 | * Analog Devices adv7176 TV encoder | |
110 | Drivers to use: videodev, i2c-core, i2c-algo-bit, | |
111 | videocodec, vpx3220/vpx3224, adv7175, zr36050, zr36015, zr36067 | |
112 | Inputs/outputs: Composite, S-video and Internal | |
113 | Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps) | |
114 | Card number: 4 | |
115 | ||
116 | Note: No module for the mse3000 is available yet | |
117 | Note: No module for the vpx3224 is available yet | |
118 | Note: use encoder=X or decoder=X for non-default i2c chips (see i2c-id.h) | |
119 | ||
120 | =========================== | |
121 | ||
122 | 1.1 What the TV decoder can do an what not | |
123 | ||
124 | The best know TV standards are NTSC/PAL/SECAM. but for decoding a frame that | |
125 | information is not enough. There are several formats of the TV standards. | |
126 | And not every TV decoder is able to handle every format. Also the every | |
127 | combination is supported by the driver. There are currently 11 different | |
128 | tv broadcast formats all aver the world. | |
129 | ||
130 | The CCIR defines parameters needed for broadcasting the signal. | |
131 | The CCIR has defined different standards: A,B,D,E,F,G,D,H,I,K,K1,L,M,N,... | |
132 | The CCIR says not much about about the colorsystem used !!! | |
133 | And talking about a colorsystem says not to much about how it is broadcast. | |
134 | ||
135 | The CCIR standards A,E,F are not used any more. | |
136 | ||
137 | When you speak about NTSC, you usually mean the standard: CCIR - M using | |
138 | the NTSC colorsystem which is used in the USA, Japan, Mexico, Canada | |
139 | and a few others. | |
140 | ||
141 | When you talk about PAL, you usually mean: CCIR - B/G using the PAL | |
142 | colorsystem which is used in many Countries. | |
143 | ||
144 | When you talk about SECAM, you mean: CCIR - L using the SECAM Colorsystem | |
145 | which is used in France, and a few others. | |
146 | ||
147 | There the other version of SECAM, CCIR - D/K is used in Bulgaria, China, | |
148 | Slovakai, Hungary, Korea (Rep.), Poland, Rumania and a others. | |
149 | ||
150 | The CCIR - H uses the PAL colorsystem (sometimes SECAM) and is used in | |
151 | Egypt, Libya, Sri Lanka, Syrain Arab. Rep. | |
152 | ||
153 | The CCIR - I uses the PAL colorsystem, and is used in Great Britain, Hong Kong, | |
154 | Ireland, Nigeria, South Africa. | |
155 | ||
156 | The CCIR - N uses the PAL colorsystem and PAL frame size but the NTSC framerate, | |
157 | and is used in Argentinia, Uruguay, an a few others | |
158 | ||
159 | We do not talk about how the audio is broadcast ! | |
160 | ||
161 | A rather good sites about the TV standards are: | |
162 | http://www.sony.jp/ServiceArea/Voltage_map/ | |
163 | http://info.electronicwerkstatt.de/bereiche/fernsehtechnik/frequenzen_und_normen/Fernsehnormen/ | |
164 | and http://www.cabl.com/restaurant/channel.html | |
165 | ||
166 | Other weird things around: NTSC 4.43 is a modificated NTSC, which is mainly | |
167 | used in PAL VCR's that are able to play back NTSC. PAL 60 seems to be the same | |
168 | as NTSC 4.43 . The Datasheets also talk about NTSC 44, It seems as if it would | |
169 | be the same as NTSC 4.43. | |
170 | NTSC Combs seems to be a decoder mode where the decoder uses a comb filter | |
171 | to split coma and luma instead of a Delay line. | |
172 | ||
173 | But I did not defiantly find out what NTSC Comb is. | |
174 | ||
175 | Philips saa7111 TV decoder | |
176 | was introduced in 1997, is used in the BUZ and | |
177 | can handle: PAL B/G/H/I, PAL N, PAL M, NTSC M, NTSC N, NTSC 4.43 and SECAM | |
178 | ||
179 | Philips saa7110a TV decoder | |
180 | was introduced in 1995, is used in the Pinnacle/Miro DC10(new), DC10+ and | |
181 | can handle: PAL B/G, NTSC M and SECAM | |
182 | ||
183 | Philips saa7114 TV decoder | |
184 | was introduced in 2000, is used in the LML33R10 and | |
185 | can handle: PAL B/G/D/H/I/N, PAL N, PAL M, NTSC M, NTSC 4.43 and SECAM | |
186 | ||
187 | Brooktree bt819 TV decoder | |
188 | was introduced in 1996, and is used in the LML33 and | |
189 | can handle: PAL B/D/G/H/I, NTSC M | |
190 | ||
191 | Micronas vpx3220a TV decoder | |
192 | was introduced in 1996, is used in the DC30 and DC30+ and | |
193 | can handle: PAL B/G/H/I, PAL N, PAL M, NTSC M, NTSC 44, PAL 60, SECAM,NTSC Comb | |
194 | ||
195 | =========================== | |
196 | ||
197 | 1.2 What the TV encoder can do an what not | |
198 | ||
199 | The TV encoder are doing the "same" as the decoder, but in the oder direction. | |
200 | You feed them digital data and the generate a Composite or SVHS signal. | |
201 | For information about the colorsystems and TV norm take a look in the | |
202 | TV decoder section. | |
203 | ||
204 | Philips saa7185 TV Encoder | |
205 | was introduced in 1996, is used in the BUZ | |
206 | can generate: PAL B/G, NTSC M | |
207 | ||
208 | Brooktree bt856 TV Encoder | |
209 | was introduced in 1994, is used in the LML33 | |
210 | can generate: PAL B/D/G/H/I/N, PAL M, NTSC M, PAL-N (Argentina) | |
211 | ||
212 | Analog Devices adv7170 TV Encoder | |
213 | was introduced in 2000, is used in the LML300R10 | |
214 | can generate: PAL B/D/G/H/I/N, PAL M, NTSC M, PAL 60 | |
215 | ||
216 | Analog Devices adv7175 TV Encoder | |
217 | was introduced in 1996, is used in the DC10, DC10+, DC10 old, DC30, DC30+ | |
218 | can generate: PAL B/D/G/H/I/N, PAL M, NTSC M | |
219 | ||
220 | ITT mse3000 TV encoder | |
221 | was introduced in 1991, is used in the DC10 old | |
222 | can generate: PAL , NTSC , SECAM | |
223 | ||
224 | The adv717x, should be able to produce PAL N. But you find nothing PAL N | |
d533f671 | 225 | specific in the registers. Seem that you have to reuse a other standard |
1da177e4 LT |
226 | to generate PAL N, maybe it would work if you use the PAL M settings. |
227 | ||
228 | ========================== | |
229 | ||
230 | 2. How do I get this damn thing to work | |
231 | ||
232 | Load zr36067.o. If it can't autodetect your card, use the card=X insmod | |
233 | option with X being the card number as given in the previous section. | |
234 | To have more than one card, use card=X1[,X2[,X3,[X4[..]]]] | |
235 | ||
236 | To automate this, add the following to your /etc/modprobe.conf: | |
237 | ||
238 | options zr36067 card=X1[,X2[,X3[,X4[..]]]] | |
239 | alias char-major-81-0 zr36067 | |
240 | ||
241 | One thing to keep in mind is that this doesn't load zr36067.o itself yet. It | |
242 | just automates loading. If you start using xawtv, the device won't load on | |
243 | some systems, since you're trying to load modules as a user, which is not | |
244 | allowed ("permission denied"). A quick workaround is to add 'Load "v4l"' to | |
245 | XF86Config-4 when you use X by default, or to run 'v4l-conf -c <device>' in | |
246 | one of your startup scripts (normally rc.local) if you don't use X. Both | |
247 | make sure that the modules are loaded on startup, under the root account. | |
248 | ||
249 | =========================== | |
250 | ||
251 | 3. What mainboard should I use (or why doesn't my card work) | |
252 | ||
253 | <insert lousy disclaimer here>. In short: good=SiS/Intel, bad=VIA. | |
254 | ||
255 | Experience tells us that people with a Buz, on average, have more problems | |
256 | than users with a DC10+/LML33. Also, it tells us that people owning a VIA- | |
257 | based mainboard (ktXXX, MVP3) have more problems than users with a mainboard | |
258 | based on a different chipset. Here's some notes from Andrew Stevens: | |
259 | -- | |
260 | Here's my experience of using LML33 and Buz on various motherboards: | |
261 | ||
262 | VIA MVP3 | |
263 | Forget it. Pointless. Doesn't work. | |
264 | Intel 430FX (Pentium 200) | |
265 | LML33 perfect, Buz tolerable (3 or 4 frames dropped per movie) | |
266 | Intel 440BX (early stepping) | |
267 | LML33 tolerable. Buz starting to get annoying (6-10 frames/hour) | |
268 | Intel 440BX (late stepping) | |
269 | Buz tolerable, LML3 almost perfect (occasional single frame drops) | |
270 | SiS735 | |
271 | LML33 perfect, Buz tolerable. | |
272 | VIA KT133(*) | |
273 | LML33 starting to get annoying, Buz poor enough that I have up. | |
274 | ||
275 | Both 440BX boards were dual CPU versions. | |
276 | -- | |
277 | Bernhard Praschinger later added: | |
278 | -- | |
279 | AMD 751 | |
280 | Buz perfect-tolerable | |
281 | AMD 760 | |
282 | Buz perfect-tolerable | |
283 | -- | |
284 | In general, people on the user mailinglist won't give you much of a chance | |
285 | if you have a VIA-based motherboard. They may be cheap, but sometimes, you'd | |
286 | rather want to spend some more money on better boards. In general, VIA | |
287 | mainboard's IDE/PCI performance will also suck badly compared to others. | |
288 | You'll noticed the DC10+/DC30+ aren't mentioned anywhere in the overview. | |
289 | Basically, you can assume that if the Buz works, the LML33 will work too. If | |
290 | the LML33 works, the DC10+/DC30+ will work too. They're most tolerant to | |
291 | different mainboard chipsets from all of the supported cards. | |
292 | ||
293 | If you experience timeouts during capture, buy a better mainboard or lower | |
294 | the quality/buffersize during capture (see 'Concerning buffer sizes, quality, | |
295 | output size etc.'). If it hangs, there's little we can do as of now. Check | |
296 | your IRQs and make sure the card has its own interrupts. | |
297 | ||
298 | =========================== | |
299 | ||
300 | 4. Programming interface | |
301 | ||
302 | This driver conforms to video4linux and video4linux2, both can be used to | |
303 | use the driver. Since video4linux didn't provide adequate calls to fully | |
304 | use the cards' features, we've introduced several programming extensions, | |
305 | which are currently officially accepted in the 2.4.x branch of the kernel. | |
306 | These extensions are known as the v4l/mjpeg extensions. See zoran.h for | |
307 | details (structs/ioctls). | |
308 | ||
309 | Information - video4linux: | |
310 | http://roadrunner.swansea.linux.org.uk/v4lapi.shtml | |
311 | Documentation/video4linux/API.html | |
312 | /usr/include/linux/videodev.h | |
313 | ||
314 | Information - video4linux/mjpeg extensions: | |
315 | ./zoran.h | |
316 | (also see below) | |
317 | ||
318 | Information - video4linux2: | |
319 | http://www.thedirks.org/v4l2/ | |
320 | /usr/include/linux/videodev2.h | |
321 | http://www.bytesex.org/v4l/ | |
322 | ||
323 | More information on the video4linux/mjpeg extensions, by Serguei | |
324 | Miridonovi and Rainer Johanni: | |
325 | -- | |
326 | The ioctls for that interface are as follows: | |
327 | ||
328 | BUZIOC_G_PARAMS | |
329 | BUZIOC_S_PARAMS | |
330 | ||
331 | Get and set the parameters of the buz. The user should always do a | |
332 | BUZIOC_G_PARAMS (with a struct buz_params) to obtain the default | |
333 | settings, change what he likes and then make a BUZIOC_S_PARAMS call. | |
334 | ||
335 | BUZIOC_REQBUFS | |
336 | ||
337 | Before being able to capture/playback, the user has to request | |
338 | the buffers he is wanting to use. Fill the structure | |
339 | zoran_requestbuffers with the size (recommended: 256*1024) and | |
340 | the number (recommended 32 up to 256). There are no such restrictions | |
341 | as for the Video for Linux buffers, you should LEAVE SUFFICIENT | |
342 | MEMORY for your system however, else strange things will happen .... | |
343 | On return, the zoran_requestbuffers structure contains number and | |
344 | size of the actually allocated buffers. | |
345 | You should use these numbers for doing a mmap of the buffers | |
346 | into the user space. | |
347 | The BUZIOC_REQBUFS ioctl also makes it happen, that the next mmap | |
348 | maps the MJPEG buffer instead of the V4L buffers. | |
349 | ||
350 | BUZIOC_QBUF_CAPT | |
351 | BUZIOC_QBUF_PLAY | |
352 | ||
353 | Queue a buffer for capture or playback. The first call also starts | |
354 | streaming capture. When streaming capture is going on, you may | |
355 | only queue further buffers or issue syncs until streaming | |
356 | capture is switched off again with a argument of -1 to | |
357 | a BUZIOC_QBUF_CAPT/BUZIOC_QBUF_PLAY ioctl. | |
358 | ||
359 | BUZIOC_SYNC | |
360 | ||
361 | Issue this ioctl when all buffers are queued. This ioctl will | |
362 | block until the first buffer becomes free for saving its | |
363 | data to disk (after BUZIOC_QBUF_CAPT) or for reuse (after BUZIOC_QBUF_PLAY). | |
364 | ||
365 | BUZIOC_G_STATUS | |
366 | ||
367 | Get the status of the input lines (video source connected/norm). | |
368 | ||
369 | For programming example, please, look at lavrec.c and lavplay.c code in | |
370 | lavtools-1.2p2 package (URL: http://www.cicese.mx/~mirsev/DC10plus/) | |
371 | and the 'examples' directory in the original Buz driver distribution. | |
372 | ||
373 | Additional notes for software developers: | |
374 | ||
375 | The driver returns maxwidth and maxheight parameters according to | |
376 | the current TV standard (norm). Therefore, the software which | |
377 | communicates with the driver and "asks" for these parameters should | |
378 | first set the correct norm. Well, it seems logically correct: TV | |
379 | standard is "more constant" for current country than geometry | |
380 | settings of a variety of TV capture cards which may work in ITU or | |
381 | square pixel format. Remember that users now can lock the norm to | |
382 | avoid any ambiguity. | |
383 | -- | |
384 | Please note that lavplay/lavrec are also included in the MJPEG-tools | |
385 | (http://mjpeg.sf.net/). | |
386 | ||
387 | =========================== | |
388 | ||
389 | 5. Applications | |
390 | ||
391 | Applications known to work with this driver: | |
392 | ||
393 | TV viewing: | |
394 | * xawtv | |
395 | * kwintv | |
396 | * probably any TV application that supports video4linux or video4linux2. | |
397 | ||
398 | MJPEG capture/playback: | |
399 | * mjpegtools/lavtools (or Linux Video Studio) | |
400 | * gstreamer | |
401 | * mplayer | |
402 | ||
403 | General raw capture: | |
404 | * xawtv | |
405 | * gstreamer | |
406 | * probably any application that supports video4linux or video4linux2 | |
407 | ||
408 | Video editing: | |
409 | * Cinelerra | |
410 | * MainActor | |
411 | * mjpegtools (or Linux Video Studio) | |
412 | ||
413 | =========================== | |
414 | ||
415 | 6. Concerning buffer sizes, quality, output size etc. | |
416 | ||
417 | The zr36060 can do 1:2 JPEG compression. This is really the theoretical | |
418 | maximum that the chipset can reach. The driver can, however, limit compression | |
419 | to a maximum (size) of 1:4. The reason for this is that some cards (e.g. Buz) | |
420 | can't handle 1:2 compression without stopping capture after only a few minutes. | |
421 | With 1:4, it'll mostly work. If you have a Buz, use 'low_bitrate=1' to go into | |
422 | 1:4 max. compression mode. | |
423 | ||
424 | 100% JPEG quality is thus 1:2 compression in practice. So for a full PAL frame | |
425 | (size 720x576). The JPEG fields are stored in YUY2 format, so the size of the | |
426 | fields are 720x288x16/2 bits/field (2 fields/frame) = 207360 bytes/field x 2 = | |
427 | 414720 bytes/frame (add some more bytes for headers and DHT (huffman)/DQT | |
428 | (quantization) tables, and you'll get to something like 512kB per frame for | |
429 | 1:2 compression. For 1:4 compression, you'd have frames of half this size. | |
430 | ||
431 | Some additional explanation by Martin Samuelsson, which also explains the | |
432 | importance of buffer sizes: | |
433 | -- | |
434 | > Hmm, I do not think it is really that way. With the current (downloaded | |
435 | > at 18:00 Monday) driver I get that output sizes for 10 sec: | |
436 | > -q 50 -b 128 : 24.283.332 Bytes | |
437 | > -q 50 -b 256 : 48.442.368 | |
438 | > -q 25 -b 128 : 24.655.992 | |
439 | > -q 25 -b 256 : 25.859.820 | |
440 | ||
441 | I woke up, and can't go to sleep again. I'll kill some time explaining why | |
442 | this doesn't look strange to me. | |
443 | ||
444 | Let's do some math using a width of 704 pixels. I'm not sure whether the Buz | |
445 | actually use that number or not, but that's not too important right now. | |
446 | ||
447 | 704x288 pixels, one field, is 202752 pixels. Divided by 64 pixels per block; | |
448 | 3168 blocks per field. Each pixel consist of two bytes; 128 bytes per block; | |
449 | 1024 bits per block. 100% in the new driver mean 1:2 compression; the maximum | |
450 | output becomes 512 bits per block. Actually 510, but 512 is simpler to use | |
451 | for calculations. | |
452 | ||
453 | Let's say that we specify d1q50. We thus want 256 bits per block; times 3168 | |
454 | becomes 811008 bits; 101376 bytes per field. We're talking raw bits and bytes | |
455 | here, so we don't need to do any fancy corrections for bits-per-pixel or such | |
456 | things. 101376 bytes per field. | |
457 | ||
458 | d1 video contains two fields per frame. Those sum up to 202752 bytes per | |
459 | frame, and one of those frames goes into each buffer. | |
460 | ||
461 | But wait a second! -b128 gives 128kB buffers! It's not possible to cram | |
462 | 202752 bytes of JPEG data into 128kB! | |
463 | ||
464 | This is what the driver notice and automatically compensate for in your | |
465 | examples. Let's do some math using this information: | |
466 | ||
467 | 128kB is 131072 bytes. In this buffer, we want to store two fields, which | |
468 | leaves 65536 bytes for each field. Using 3168 blocks per field, we get | |
469 | 20.68686868... available bytes per block; 165 bits. We can't allow the | |
470 | request for 256 bits per block when there's only 165 bits available! The -q50 | |
471 | option is silently overridden, and the -b128 option takes precedence, leaving | |
472 | us with the equivalence of -q32. | |
473 | ||
474 | This gives us a data rate of 165 bits per block, which, times 3168, sums up | |
475 | to 65340 bytes per field, out of the allowed 65536. The current driver has | |
476 | another level of rate limiting; it won't accept -q values that fill more than | |
477 | 6/8 of the specified buffers. (I'm not sure why. "Playing it safe" seem to be | |
478 | a safe bet. Personally, I think I would have lowered requested-bits-per-block | |
479 | by one, or something like that.) We can't use 165 bits per block, but have to | |
480 | lower it again, to 6/8 of the available buffer space: We end up with 124 bits | |
481 | per block, the equivalence of -q24. With 128kB buffers, you can't use greater | |
482 | than -q24 at -d1. (And PAL, and 704 pixels width...) | |
483 | ||
484 | The third example is limited to -q24 through the same process. The second | |
485 | example, using very similar calculations, is limited to -q48. The only | |
486 | example that actually grab at the specified -q value is the last one, which | |
487 | is clearly visible, looking at the file size. | |
488 | -- | |
489 | ||
490 | Conclusion: the quality of the resulting movie depends on buffer size, quality, | |
491 | whether or not you use 'low_bitrate=1' as insmod option for the zr36060.c | |
492 | module to do 1:4 instead of 1:2 compression, etc. | |
493 | ||
494 | If you experience timeouts, lowering the quality/buffersize or using | |
495 | 'low_bitrate=1 as insmod option for zr36060.o might actually help, as is | |
496 | proven by the Buz. | |
497 | ||
498 | =========================== | |
499 | ||
500 | 7. It hangs/crashes/fails/whatevers! Help! | |
501 | ||
502 | Make sure that the card has its own interrupts (see /proc/interrupts), check | |
503 | the output of dmesg at high verbosity (load zr36067.o with debug=2, | |
504 | load all other modules with debug=1). Check that your mainboard is favorable | |
505 | (see question 2) and if not, test the card in another computer. Also see the | |
506 | notes given in question 3 and try lowering quality/buffersize/capturesize | |
507 | if recording fails after a period of time. | |
508 | ||
509 | If all this doesn't help, give a clear description of the problem including | |
510 | detailed hardware information (memory+brand, mainboard+chipset+brand, which | |
511 | MJPEG card, processor, other PCI cards that might be of interest), give the | |
512 | system PnP information (/proc/interrupts, /proc/dma, /proc/devices), and give | |
513 | the kernel version, driver version, glibc version, gcc version and any other | |
514 | information that might possibly be of interest. Also provide the dmesg output | |
515 | at high verbosity. See 'Contacting' on how to contact the developers. | |
516 | ||
517 | =========================== | |
518 | ||
519 | 8. Maintainers/Contacting | |
520 | ||
521 | The driver is currently maintained by Laurent Pinchart and Ronald Bultje | |
522 | (<laurent.pinchart@skynet.be> and <rbultje@ronald.bitfreak.net>). For bug | |
523 | reports or questions, please contact the mailinglist instead of the developers | |
524 | individually. For user questions (i.e. bug reports or how-to questions), send | |
525 | an email to <mjpeg-users@lists.sf.net>, for developers (i.e. if you want to | |
526 | help programming), send an email to <mjpeg-developer@lists.sf.net>. See | |
527 | http://www.sf.net/projects/mjpeg/ for subscription information. | |
528 | ||
529 | For bug reports, be sure to include all the information as described in | |
530 | the section 'It hangs/crashes/fails/whatevers! Help!'. Please make sure | |
531 | you're using the latest version (http://mjpeg.sf.net/driver-zoran/). | |
532 | ||
533 | Previous maintainers/developers of this driver include Serguei Miridonov | |
534 | <mirsev@cicese.mx>, Wolfgang Scherr <scherr@net4you.net>, Dave Perks | |
535 | <dperks@ibm.net> and Rainer Johanni <Rainer@Johanni.de>. | |
536 | ||
537 | =========================== | |
538 | ||
539 | 9. License | |
540 | ||
541 | This driver is distributed under the terms of the General Public License. | |
542 | ||
543 | This program is free software; you can redistribute it and/or modify | |
544 | it under the terms of the GNU General Public License as published by | |
545 | the Free Software Foundation; either version 2 of the License, or | |
546 | (at your option) any later version. | |
547 | ||
548 | This program is distributed in the hope that it will be useful, | |
549 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
550 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
551 | GNU General Public License for more details. | |
552 | ||
553 | You should have received a copy of the GNU General Public License | |
554 | along with this program; if not, write to the Free Software | |
555 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
556 | ||
557 | See http://www.gnu.org/ for more information. |