[android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
Problems in 'fill_plasma': 1. The raw data of the *pxl*-array can not contain JPEG encoded data. Instead it must be encoded as RGB_565, each 2 bytes having 5 bits of red, 6 bits of green and 5 bits of blue. 2. You can not assign the bitmap's raw-data array address (*pxl*) to your compressed buffer-address. Instead, you'll have to copy each individual pixel from '*buf*' into '*pxl*'. Use a for-loop and copy each byte from the *buf*-array into *pxl*-array. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
See my answer in 'android-developers' group. Please, don't cross-post. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
On Mon Dec 19 06:50:53 2011, Streets Of Boston wrote: See my answer in 'android-developers' group. Please, don't cross-post. A) I'd already answered essentially the same thing, but doesn't hurt to say it again in a different way. B) You mean the message that you cross-posted? Date: Mon, 19 Dec 2011 06:49:21 -0800 (PST) From: Streets Of Boston flyingdutc...@gmail.com Reply-To: android-...@googlegroups.com To: android-developers@googlegroups.com Cc: android-...@googlegroups.com, android-disc...@googlegroups.com Message-ID: 23786539.1588.1324306161440.JavaMail.geo-discussion-forums@vbxw7 In-Reply-To: CALwa49tNdJaeu0-ef4PvfMSdwfHX6gkoud8DLj4r7A+WNVw9=w...@mail.gmail.com References: CALwa49tNdJaeu0-ef4PvfMSdwfHX6gkoud8DLj4r7A+WNVw9=w...@mail.gmail.com Subject: Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i?? Problems in 'fill_plasma': 1. The raw data of the *pxl*-array can not contain JPEG encoded data. Instead it must be encoded as RGB_565, each 2 bytes having 5 bits of red, 6 bits of green and 5 bits of blue. 2. You can not assign the bitmap's raw-data array address (*pxl*) to your compressed buffer-address. Instead, you'll have to copy each individual pixel from '*buf*' into '*pxl*'. Use a for-loop and copy each byte from the *buf*-array into *pxl*-array. ;-) sdw -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
The cross-posting remark wasn't targeted at you, Stephen. It was for the original poster :-) BTW: All the answers that we post on one forum will automatically be cross-posted on the other two forums as well (i guess because the original message was cross-posted) unless you uncheck some Cc check-boxes (whose existence i've just discovered :-)). -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
Stephen/SoB , i admit for cross-posting/rephrasing the question.Sincere apologies. btw still struggling to get this work.But once done will post the experience here. warm thanks to you both !! Rgds, Saurabh ..pain is temporary.quitting lasts forever.. On Tue, Dec 20, 2011 at 12:12 AM, Streets Of Boston flyingdutc...@gmail.com wrote: The cross-posting remark wasn't targeted at you, Stephen. It was for the original poster :-) BTW: All the answers that we post on one forum will automatically be cross-posted on the other two forums as well (i guess because the original message was cross-posted) unless you uncheck some Cc check-boxes (whose existence i've just discovered :-)). -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
Hi Stephen, thanks for the reply, Can you Plz elaborate the methods and this in your last sentence -- There are *fast built-in methods* to do *this* well, but basically you create a pixel from a weighted average in color space of the pixels that the resulting pixel overlaps a ltmgfy link will be great !!! Rgds, Saurabh ..pain is temporary.quitting lasts forever.. On Sun, Dec 18, 2011 at 3:07 AM, Stephen Williams stephendwilli...@gmail.com wrote: There are fast built-in methods to do this well, but basically you create a pixel from a weighted average in color space of the pixels that the resulting pixel overlaps. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
http://developer.android.com/reference/android/graphics/Bitmap.html#createScaledBitmap%28android.graphics.Bitmap,%20int,%20int,%20boolean%29 Many things in Java, especially graphics operations, are implemented mainly by native code. I've traced 2D graphics calls all the way down to very specific JNI calls for particular transformations or bitblit or whatever. So, there's often little point in writing your own native code to implement something that the libraries already do since often they are well optimized. If you want to do something not already included, then it can make sense to go native. sdw On Sun Dec 18 21:27:02 2011, s.rawat wrote: Hi Stephen, thanks for the reply, Can you Plz elaborate the methods and this in your last sentence -- There are *fast built-in methods* to do *this* well, but basically you create a pixel from a weighted average in color space of the pixels that the resulting pixel overlaps a ltmgfy link will be great !!! Rgds, Saurabh ..pain is temporary.quitting lasts forever.. On Sun, Dec 18, 2011 at 3:07 AM, Stephen Williams stephendwilli...@gmail.com mailto:stephendwilli...@gmail.com wrote: There are fast built-in methods to do this well, but basically you create a pixel from a weighted average in color space of the pixels that the resulting pixel overlaps. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: SENDING YUV-TO-JPEG CONVERTED BUFFER AS A BITMAP from JNI to Android code...plzzz help...Not a Noob , Am i??
This line gives you a pointer to the pixel buffer in the Bitmap:
if ((ret = AndroidBitmap_lockPixels(env, bitmap, pixels)) 0) {
Then you pass it into your drawing method:
fill_plasma(info, pixels );
void fill_plasma( AndroidBitmapInfo* info, unsigned char* pxl )
Then you allocate, at the C level, a completely different buffer:
unsigned char* buf = (unsigned char* )malloc(pvideoBuff-framesizeIn);
Then you compress your capture buffer into jpeg data (a compressed image
format, not a bitmap buffer) into that temporary buffer:
compress_yuyv_to_jpeg(pvideoBuff, buf, pvideoBuff-framesizeIn, 80, pvideoBuff-formatIn); //method to convert raw data
into jpeg format- Quiet popular code on the
Then you overwrite the temporary parameter variable pxl with the address of the
resulting buffer.
You never got around to changing the bytes in the Bitmap buffer that you locked and unlocked. And even if you had, you were
working with Jpeg compressed data that would have been garbage as a Bitmap. Bitmaps are simple arrays of bytes representing
uncompressed pixels. Additionally, malloc() allocated data is not something you pass back to Java to manage. You should copy
into Java-allocated buffers.
If the capture buffer is the same size as the bitmap, you simply need to map each pixel using yuv-RGB formulas. If they are
different sizes, you need to resize the image too. There are fast built-in methods to do this well, but basically you create a
pixel from a weighted average in color space of the pixels that the resulting pixel overlaps.
sdw
On 12/17/11 10:59 AM, s.rawat wrote:
HI,
I have been trying hard from past four nights to get this thing work but so far not able to do that.I have taken and modified
few of the code from the ndk-sample(in the samples directory in the ndk r7) for plasma -sample for passing and mapping the
bitmap from the JNI.
Following is my code snippet :
*Android : *
#this code is running in a thread
Bitmap mBitmap = Bitmap.createBitmap(320,240, Bitmap.Config.RGB_565);
renderPlasma(mBitmap);
#this code is running in a thread
*Native : *
Java_my_package_name_DrawCanvas_renderPlasma(JNIEnv * env, jobject obj,
jobject bitmap)
{
AndroidBitmapInfo info;
unsigned char**pixels;
intret =10;
if ((ret = AndroidBitmap_getInfo(env, bitmap, info)) 0) {
return;
}
if (info.format != ANDROID_BITMAP_FORMAT_RGB_565) {
return;
}
if ((ret = AndroidBitmap_lockPixels(env, bitmap, pixels)) 0) {
return;
}
/* Now fill the values with a nice little plasma */
fill_plasma(info, pixels );
AndroidBitmap_unlockPixels(env, bitmap);//i am hoping that the bitmap has been mapped to the contents of pixel at this
point.
}
struct vdIn *pvideoBuff = 0;//v4l2 structure which contains the raw YUV data
void fill_plasma( AndroidBitmapInfo* info, unsigned char* pxl )
{
unsigned char* buf = (unsigned char* )malloc(pvideoBuff-framesizeIn);
uvc_startCapture(pvideoBuff);//v4l2 function which returns the raw yuc data
form the uvc compliant webcamera
compress_yuyv_to_jpeg(pvideoBuff, buf, pvideoBuff-framesizeIn, 80, pvideoBuff-formatIn); //method to convert raw data
into jpeg format- Quiet popular code on the web
pxl = buf;//i am thinking the pxl will have now all the contents of the
jpeg converted buffer
}
//the bitmap being returned from the native code has to be drawn on the bitmap
continuously.
canvas.drawBitmap(mBitmap, 0,0, null);
I suspect that pixel being a 2D array , I have to assisgn each array elements from the buf.Plz correct me or slap a rockstar
reply to this problem.
Best Rgds and Thanks in advance
Softy
..pain is temporary.quitting lasts forever..
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