DM368支持視頻的縮放功能,例如DM365可以編碼一個720P的,同時可以以任意分辨率(小于720P的分辨率)輸出。其中有兩種模式:IMP_MODE_SINGLE_SHOT,IMP_MODE_CONTINUOUS.
在用dm365的時候,用resizer的ioctl,一直不好使,后來在ti論壇上看到一個人的講解,原來是bootargs的錯。
在配置的時候,有一項dm365_imp.oper_mode=1,這個要配成1.
下面是我的配置,僅供參考
setenv bootargs mem=80M console=ttyS0,115200n8 noinitrd rw ip=192.168.0.7:192.168.0.1:255.255.255.0 nfsroot=192.168.0.8:/home/mick/davinci/nfs_filesystem/dm365_filesys davinci_enc_mngr.ch0_output=LCD video=davincifb:vid0=720x480x16,2025K@0,0:osd0=720x480x16,1350K@0,0 davinci_capture.device_type=4 dm365_imp.oper_mode=1
DM365同時實現H.264和JPEG雙碼流輸出
DM365的HDVCP和IMCOP是兩個獨立單元,H.264編碼和JPEG編碼運行在兩個不同的硬件引擎,但是目前TI的編碼庫(H.264和JPEG)共享一些資源,比如EDMA通道和內存等。因為這個原因,要在DM365上實現H.264和JPEG雙碼流輸出,就得讓二者按序運行。TI目前提供了一些機制來并行輸出雙碼流,相應的設置流程為:
1. Use scratchGroup Id = 1 for H.264 encoder, scratchGroupId = 2 for JPEG in your .cfg file
2. Release some EDMA channels from the kernel. You have to free atleast 4-6 channels and it can be done in edma.c in the linux kernel source code. The choice of channels to remove depends on your use case and the peripherals you use.
3. Turn on enableDDR parameter of H.264 encoder.
If you have IPNC Reference Design software, you can refer to it for item #1 and #3. But in IPNC also, we do not run JPEG and H.264 in parallel.
Please note that MPEG4 and H.264 cannot run in parallel due to EDMA channel limitation, so keep them both in some scratchGroupId.
dm365的resizer使用
在用dm365的時候,用resizer的ioctl,一直不好使,后來在ti論壇上看到一個人的講解,原來是bootargs的錯。在配置的時候,有一項dm365_imp.oper_mode=1,這個要配成1.
下面是我的配置,僅供參考
setenv bootargs mem=64M console=ttyS0,115200n8 noinitrd rw ip=192.168.0.7:192.168.0.1:255.255.255.0 nfsroot=192.168.0.8:/home/mick/davinci/nfs_filesystem/dm365_filesys davinci_enc_mngr.ch0_output=LCD video=davincifb:vid0=720x480x16,2025K@0,0:osd0=720x480x16,1350K@0,0 davinci_capture.device_type=4 dm365_imp.oper_mode=1