How to use MJPEG hardware decoder in Android with IMX6Q

[jojorong]

Hi,

     RT,

     I am a newbie in Android,

     Someone know about how to use MJPEG hardware decoder in native code in android ?

     I hope i can use middle software to invoke indirectly the hardware decoder also like in linux platform.

     I know about that i can use gstreamer or libvpu directly in Linux platform.

     also, i saw the configure file in /etc/media_codecs.xml, there is not "MJPEG" information, the MJPEG is not supported in "android_jb4.2.2_1.1.0-ga_image_6qsabresd" ?

[LeonardoSandova]

Hi

Use OpenMax IL, this is a thin layer wrapping all codecs in Android. I am not a Android expert but I would start grepping for openmax strings under Android source folder.

Leo

[jojorong]

Hi,

     As you said i can use OpenMax IL, what's the component name of MJPEG HW decoder ?

i saw the source code of other chip like TI, it looks like bellow :

     char *tComponentName[MAXCOMP][2] = {

    /*video and image components */

    {"OMX.TI.JPEG.decoder", "image_decoder.jpeg" },

about IMX6Q-SDB, what's the component name of MJPEG HW decoder ?

and which library i can use as the "libopenmax_il.so" in this board ?

[LeonardoSandova]

Hi,

I do not much about the MM Framework on Android.ChucoChe, are there any test units using OpenMax IL layer? Where is it on the source tree?

Leo

[ChucoChe]

I don't know. Maybe DaianeAngolini Knows.

:smileyhappy:    

Michel

[daiane_angolini]

If you go to Gallery and play a movie it will be accelerated.

If you see Gallery source code, you can learn the media player class (I really do not remember, if it´s media_player, movie_player, movie_start... something like that)

If you´re looking for implementing your own media player, you must use this "media player class", that should be hardware accelerated already.

What do you want to do?

[jojorong]

i want to use the HW MJPEG decoder to decode my image from internet in NDK space (c code)

[jojorong]

I have no source code of android platform,

I use the OpenMax IL directly, some error is reported when i do (disable the port):

OMX_SendCommand (comp->handle, OMX_CommandPortDisable,

        port->index, NULL);

  if (err != OMX_ErrorNone) {

    GST_ERROR_OBJECT (comp->parent,

        "Failed to send enable/disable command to %s port %u: %s (0x%08x)",

        comp->name, port->index, gst_omx_error_to_string (err), err);

    goto done;

the error is "OMX_ErrorNotReady", what's something wrong about for this error about for VPU ?

[DraganOstojic]

Daiane, I have a related question. JPEG capture image ends up in the in Android imx6 CameraHAL (ics 4.0) JpegEncoderSoftware.cpp. JPEG encoder is called from DoEncode() method as follows:

return_val = jpeg_enc_init(obj_ptr);

...

return_val = jpeg_enc_encodeframe(obj_ptr, i_buff, y_buff, u_buff, v_buff);

From looking at Android.mk file in libcamera folder, it appears that the functions are in the following library: libfsl_jpeg_enc_arm11_elinux which is in the prebuilt folder device/fsl-proprietary/lib without the source code.

Is this api h/w accelerated?  Also, theses jpeg_... api's don't seem to be documented anywhere, can you point me for the documentation?

A note: I'd expect that the api that should be used is from vpu library with vpu_... prefix.

[jojorong]

The gstreamer project can use "android media codec" aka "amc" to decode in native code.

BTW, Have you tested with "com.android.media.codec" in the IMX6Q for all HW codec ?

[jojorong]

Ok, thanks, i also research some ways to invoke the android codec, likes gstreamer project (sdk), it works on android without HW codec :smileysad:,

i check this method first, it's common in cross-platform, is it ?