c# - Error on adjusting jpeg quality: Value cannot be null.Parameter name: structure -


i have method take image, make copy resizing, , return byte array. have attempted add ability adjust quality of image per doc:

http://msdn.microsoft.com/en-us/library/bb882583(v=vs.110).aspx

image image = image.fromfile(_filepath);  image newimage = new bitmap(newwidth, newheight); using (graphics graphicshandle = graphics.fromimage(newimage)) {     graphicshandle.interpolationmode = interpolationmode.highqualitybicubic;     graphicshandle.drawimage(image, 0, 0, newwidth, newheight); } memorystream memstream = new memorystream();  encoderparameters myencoderparameters = new encoderparameters(1);  imagecodecinfo encoder = imagecodecinfo.getimagedecoders().singleordefault(c => c.mimetype == contenttype); system.drawing.imaging.encoder myencoder = system.drawing.imaging.encoder.quality; encoderparameter myencoderparameter = new encoderparameter(myencoder, 50l); newimage.save(memstream, encoder, myencoderparameters);  return memstream.toarray();

when call newimage.save(), error:

an exception of type 'system.argumentnullexception' occurred in system.drawing.dll not handled in user code

message is:

value cannot null. parameter name: structure

msdn says have argumentnullexception when calling save() overload if stream null.

are sure no other (omitted?) code not nullifying stream? sure site of exception?


-

Comments

Post a Comment

Popular posts from this blog

android - Automated my builds -

i have multiple app , android project want automated in build , release sequence. have ant script build , create apk of app. want have 1 script or ant file start build sequence app. maybe don't konw search, can't find easy documentation on ant. the point of use jenkins ant (or maven, i'm not sure of difference between them now) automated build sequence when people commit on project. any int appreciated maven dependencies (over ant) don't need pass around jars. recommend maven on ant day. syntax , overall process easier understand, @ end of both build tools. if able to, more recommend upgrading gradle. easy create different build types , create them ./gradlew assemble here project jake wharton can see power of gradle. there release , debug build, can make lot more if like. https://github.com/jakewharton/u2020 here android docs gradle http://tools.android.com/tech-docs/new-build-system/user-guide . if can't find looking here, check out main grad...
Read more

php - Iterate over object properties with keys from second array -

i call foreach loop on object , iterate on $this->_values , keys present in $this->_allowedfields . 1) $this->_values can contain data not $this->_allowedfields , should excluded foreach. 2) $this->_allowedfields will contain keys not in $this->_values , still need include step in foreach loop. how can achieve this? i have set class implement iterator , can call foreach loop on object's _values array, so: foreach($object $key => $value) { // stuff } solution found solution myself below when implementing iterator interface. public function rewind() { reset($this->_allowedfields); } public function current() { $key = current($this->_allowedfields); return $this->_values[$key]; } public function key() { $key = current($this->_allowedfields); return $key; } public function next() { next($this->_allowedfields); $key = current($this->_allowedfields); return $this->$this->_values[...
Read more

apache - GeoServer under https -

i using apache web server on localhost:80 , geoserver served tomcat on localhost:8080 i installed ssl certificate on apache , works fine except message says have insecure content thought geoserver layers. i'm trying enable ssl geoserver , have openlayers content htis https://example.org:8080/geoserver still not sure what's best approach that.
Read more