-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 于 2014年01月02日 20:59, Kamil Debski 写道: > Hi, > >> From: lxr1234 [mailto:lxr1234@xxxxxxxxxxx] Sent: Thursday, >> January 02, 2014 1:57 PM To: Kamil Debski Subject: RE: using MFC >> memory to memery encoder, start stream and queue order problem >> >> >> >> Kamil Debski <k.debski@xxxxxxxxxxx>写到： >>> Hi Randy, >>> >>>> From: randy [mailto:lxr1234@xxxxxxxxxxx] Sent: Thursday, >>>> January 02, 2014 12:35 PM Hello >>>> >>>> I have follow the README of the v4l2-mfc-encoder from the >>>> http://git.infradead.org/users/kmpark/public-apps it seems >>>> that I can use the mfc encoder in exynos4412(using 3.5 >>> kernel >>>> from manufacturer). >>> >>> So it is not the mainline kernel. Could you give a link to >>> this >> kernel? >>> I have doubts that this kernel is using the open source driver. >>> The driver present in that kernel could be a significantly >>> modified >> driver. >>> The kernel souce code can be found here https://github.com/hizukiayaka/linux-tiny4412-origin I am pushing. >> Sorry, It doesn't in a git repo I will update,it later, the >> kernel is from friendlyarm, I see driver source in kernel. >>>> But I have a problem with the contain of the README and I >>>> can't get >>> the >>>> key frame(the I-frame in H.264). It said that "6. Enqueue >>>> CAPTURE buffers. 7. Enqueue OUTPUT buffer with first frame. >>>> 8. Start streaming (VIDIOC_STREAMON) on both ends." so I >>>> shall enqueue buffer before start stream, to enqueue a >>>> buffer, >> I >>>> need to dequeue first, but without start stream, it will >>>> failed in >>> both >>>> side. >>> >>> I think I don't understand this. You should enqueue the buffers >>> and then start streaming. I think dequeueing is not mentioned >>> here. First enqueue then dequeue. >> Without dequeue, hwo to get a buffer to fill data(first raw >> video)? And what shall enqueue in CAPTURE. Is there a guide fo >> usibg memory to memory driver? > > After doing a VIDIOC_REQBUFS you should do a VIDIOC_QUERYBUF call > to get the buffers. After that you can enqueue them. > > I suggest that you first run decoding. v4l2-mfc-example from > public-apps. This way you could see how the V4L2 framework works. > I see thank you the v4l2-mfc-encoder is so difficult that I failed to understand. My code is modified from gst's mfc decoder, I ignored that ioctl in source ;) >>>> In this way I start OUTPUT(input raw video) stream first >>>> then >> dequeue >>>> and enqueue the first frame, then I start the CAPTURE(output >>>> encoded video) frame, dequeue CAPTURE to get a buffer, get >>>> the data from >>> buffer >>>> then enqueue the buffer. The first frame of CAPTURE is always >>>> a 22 bytes frame(I don't know whether they are the same data >>>> all the time, but size is the same from >>>> m.planes[0].bytesused), but it seems not a key frame. >>>> >>>> What is the problem, and how to solve it. >>>> >>>> P.S I don't test the Linux 3.13-rc4, as the driver is not >>>> ready for encoder before. >>>> >>>> Thank you >>> >>> Best wishes, >> Thank you -- lxr1234 > > Best wishes, Kamil > > I forget to mail to the list, I just repeated to you directly as I shall CC you. Thank you very much ayaka -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJSxXGxAAoJEPb4VsMIzTziHVQH+wXTpbhxjGme1sn8f1gbPNzZ a3FDBjiVC/WiK0TW0kp1IIlV5X93vMhE/VagXIxgxv7FuNcTRYe3EKxXg96Thk4T 1svg7Cnny0FbZoCbm+2pzg5itvqowZfnQhBI71vnVWVlxHm2ub2tVha/JCtCLoW2 sXDoqg72tcdmxoAl8HqPmokGMkn5aLdVfPnOpLHfPJvNoIWCyOvpc5REutlF4uzT NjgAZMqBwjARjd0nJiLaxsuQQ3EK8d8MCZkkZTCTQLiH+SKfu/Js3nTK1CCkWhSv z82WDw5qmE3573+2+xxgACal0jPJaDynXBMd/wvBWzpLvSF/Jcg49RDS8exVQfs= =q5zX -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
