inJustDecodeBounds in BitmapFactory.Options.

On Jul 24, 9:37 pm, Agus <[email protected]> wrote:
> Sorry for going slightly off-topic, how do I determine the dimension
> of the picked gallery image without reading it first using
> DecodeBitmap.decodeStream(InputStream) method ?
> I am decoding the original image which causes OutOfMemory error frequently.
>
> On Sat, Jul 24, 2010 at 3:47 PM, DanH <[email protected]> wrote:
> > Yeah, I was assuming that the space for the bitmap is allocated in
> > Java heap, without thinking that many phones allocate graphics
> > separately. Obviously, if the bitmap is allocated outside of the Java
> > heap then freeMemory() does you zero good.  But my point was that
> > freeMemory() only returns the amount of heap not allocated to objects
> > at the moment.  If there is heap allocated to "dead" objects (that
> > would be collected by a GC) then that space is considered "allocated",
> > from the standpoint of freeMemory().  And, of course, there's no way
> > to know how much "dead" heap storage there is without actually running
> > GC.
>
> > So whether or not the bitmap is allocated in Java heap, freeMemory()
> > is not real useful, at least not without actually running a (full) GC
> > cycle first.
>
> > On Jul 24, 5:20 pm, Streets Of Boston <[email protected]> wrote:
> >> First a small correction on DanH's reply, ARGB_8888 uses 32 bits (4
> >> bytes), not 64 bits.
>
> >> The memory used by a Bitmap is roughly Width*Height*Depth bytes. (e.g.
> >> a 1MPixel image in RGB_565 uses 2MByte of memory). I say roughly,
> >> because the Bitmap object itself, holding the raw data, occupies a few
> >> bytes itself.
>
> >> The problem is that the (garbage collector of) DalvikVM does not 'see'
> >> the raw image data. It only sees the the memory usage of the Bitmap
> >> object without the raw data (a few bytes). That's why the call to
> >> 'freeMemory()' does not seem correct. It only reports the difference
> >> between the max available memory minus the memory used by Java objects
> >> (which does not include raw image data).
>
> >> However, the raw image data does affect the memory usage of your app's
> >> Linux process, which is limited to either 16MByte or 24MByte.
>
> >> E.g. if your app's free memory is 1.5MByte and you create a 2MByte
> >> Bitmap, the DalvikVM does not see the need to run the garbage
> >> collector to free up old un-referenced objects, because to DalvikVM it
> >> looks like it only needs to create a few bytes for the Bitmap object
> >> itself and does not see the danger of a possible out-of-memory
> >> situation.
>
> >> In my image-editing app, i try to mitigate this (not quite solve it),
> >> by calling a System.gc() just before creating a (relatively) large
> >> Bitmap. This reduces the chance of an out-of-memory error.
>
> >> On Jul 24, 2:03 pm, ReyLith <[email protected]> wrote:
>
> >> > First of all thank you very much everyone for your help.
>
> >> > I continue with a problem. I use Runtime.getRuntime().freeMemory() for
> >> > obtain the free memory and compare it with the real Bitmap memory.
> >> > Sometimes I get a free memory less than that occupied by the image.
> >> > However, if I remove the restriction on the size of the image, I can
> >> > work with it without any problem. Am I using an incorrect function to
> >> > get the free memory?. Should I use another function?
>
> >> > Thank you very much in advance.
>
> >> > On 23 jul, 20:40, DanH <[email protected]> wrote:
>
> >> > > Close as I can tell, you use a BitmapFactory.Options and put a
> >> > > BitmapConfig constant in that that specifies the type of internal
> >> > > representation you want.  If you use ARGB_8888 then each pixel will be
> >> > > 64 bits.  ARGB_4444 -- 32 bits, RGB_565 -- 16 bits.
>
> >> > > On Jul 23, 12:21 pm, ReyLith <[email protected]> wrote:
>
> >> > > > Thanks Nathan.
>
> >> > > > With this option I can obtain the image characteristics but I don't
> >> > > > know the option that indicates me the depth of the pixel. Width and
> >> > > > Height are in outWidth and outHeight but I don't know where is the
> >> > > > depth. I thought use the getRowBytes() of Bitmap and product it with
> >> > > > getHeight() of Bitmap, but I don't know if there is correct.
>
> >> > > > On 23 jul, 18:52, Nathan <[email protected]> wrote:
>
> >> > > > > If you can get the width and height for the image without 
> >> > > > > completely
> >> > > > > opening it, then use the width*height*depth.
>
> >> > > > > You probably have to use this option:
>
> >> > > > >http://developer.android.com/intl/de/reference/android/graphics/Bitma...
>
> >> > > > > Nathan
>
> >> > > > > On Jul 23, 9:30 am, ReyLith <[email protected]> wrote:
>
> >> > > > > > So, how can I obtain the depth for know if I can work with the 
> >> > > > > > image?
>
> >> > > > > > On 23 jul, 18:18, DanH <[email protected]> wrote:
>
> >> > > > > > > The size of an image file depends greatly on the compression
> >> > > > > > > techniques used to create it.  Virtually all image formats 
> >> > > > > > > involve
> >> > > > > > > some sort of compression such that the total number of bits in 
> >> > > > > > > the
> >> > > > > > > file is considerably less than the (width * height * depth) 
> >> > > > > > > number
> >> > > > > > > that represents the raw image.
>
> >> > > > > > > On Jul 23, 7:27 am, ReyLith <[email protected]> wrote:
>
> >> > > > > > > > Hi again,
>
> >> > > > > > > > I'm trying to put a message when the image is so big. For 
> >> > > > > > > > this I think
> >> > > > > > > > to obtain the size of the file and compare it with the free 
> >> > > > > > > > memory
> >> > > > > > > > Runtime.getRuntime().getFreeMemory()). It works well but I 
> >> > > > > > > > have a new
> >> > > > > > > > problem. The application show an error message with some 
> >> > > > > > > > images
> >> > > > > > > > because they are so big and the application dont't detect 
> >> > > > > > > > the problem.
> >> > > > > > > > I research in other posts and the problem is that the file 
> >> > > > > > > > size is
> >> > > > > > > > different from the size of the image in memory. To get the 
> >> > > > > > > > size of the
> >> > > > > > > > image in memory I use the product getHeight () * getRowBytes 
> >> > > > > > > > () of the
> >> > > > > > > > Bitmap class, but with some images not previously had 
> >> > > > > > > > problems, I get
> >> > > > > > > > very large sizes, so often I get the message erroneously.
>
> >> > > > > > > > Does anyone know how could solve this problem?
>
> >> > > > > > > >  Thank you very much in advance.- Hide quoted text -
>
> >> > - Show quoted text -
>
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