Fastest Way To Generate Thumbnails - Without Bogging Down The UI
Apr 29, 2012
The fastest way to generate thumbnails using VB.net and multiple computers without bogging down the UI. Right now I have 3 computers and I run an instance of my thumbnail generator code on each. One computer hosts the images. The other two computers access the folder of images via the network. My code is written to compare the main folder and a thumbnail folder to see if new thumbnails need to be generated. If so, a thread is generated and the thumbnail generation code is ran on the thread. There are 5 threads created in all. So, theoretically, across 3 machines, I'm getting 5 independent threads and I'm thinking that Windows 7 automatically spreads the load across the local cores. In an effort to avoid duplicating work, the comparison is done before the generation of each thumbnail.
This method is faster than using only one computer but drags down the performance on all computers (THE UI also becomes unresponsive). I'm looking for a better way to
1.) Produce the thumbnails as fast as possible
2.) Keep all UI's responsive (boy possibly controlling the priority setting) and
3.) Done within a single instance of the program.
In the #3, I mentioned that I would like to use one instance. Is it possible for networking information be used by the hosting computer that will allow threads to run on the other 2 computers? This way, the 15 threads will be controlled by a single host computer.
Here is a snippet of my
Public Sub CreateThumbsFUNCTION(ByVal IMAGE As String, ByVal MAXDIMENSION As Integer)
'following code resizes picture to fit.
'IMAGE needs the full path
'If thumbnail already exists, it will skip
I have a program that scrap websites and "puts" the information into a table.
My problem is that now and then i get values that i already have in the table. to avoid getting duplicates i search thru the table first to see if the value exist or if the record exist but might be in need of getting updated.
My table contains 60 000 records and is growing.
first i filtered a datagrid but it takes to long so i used the "select" method on the dataset table but it takes longer.
the program loops thru thousands of websites so it'll be doing a search for every website and the added time to collect the data just takes too long.
When I have many controls on a Form (i.e. Label, Button etc) that do almost the same thing, I often use one method to handle all the controls Click, MouseDown, MouseUp events.But to know which of the controls throwing the event and access the properties of that control I need to cast the "sender" object to the correct type.
The thing is that I always know which type it is, I don't really have to "TryCast", "DirectCast" and check if the operation returns true. I some times use CType as well.
I've an arraylist having 30000 items in it, what's the best way of creating a text file on the fly from an ASP.NEt page? Currently I'm using the code below but it times out with large data,[code]
I have a pixel I want to monitor for change. For example, first it is white, and suddenly it is black, and then changes back to white. My method is not fast enough to get this change.any changes I call the function below to get the original color of the pixel. Then I have a timer that runs every 1 ms to take the color of the pixel, and if it's not equal to original color; do something. For example counts the time the pixel has changed. However, this function does not run fast enough. Is there any faster methods to check the pixel? The function returns an ARGB code of the pixel color.[code]....
I was wondering if anyone had a better(faster) way to parse a Tab delimited file in VB.net. I need to read a file into an SQL table and the file contains about 300,000+ rows. Takes quiet a while. at the moment i have the below [Code].
I am quite new at VB.NET and just need helo on sorting algorithms, prferbly the fastest (quick sort) but bubble would so. It is for sorting and array for 12 numbers, which are being enter by the user via a input box. These are then transfered onto a listbox for visual aid. so the steps involved would be: (already done)1) Enter then inputs into array via inputbox2) Input to sppear in listbox (not done)3) Sort the array ascending/decending4) print results into the listbox again.In my code there is also a total and a average, but that doesnt need any help on it. [code]
ive a folder with a few hundred .rtf documents. am making a program to search some text in them.the way currently im employing is having a richtextbox on my form and serially loading each file in the richtextbox and if the search text is found in it,adding it to a list.but this is time taking,
In my project I have 3 different forms. They all have the same design layout so the only different you see is where the text boxes and buttons are placed. Right now I have 3 buttons at the top of each form that Im using to switch between the forms
[Code]...
I know there is probably a much better way of doing this, and faster. I dont' like the delay between each window showing/hiding. what options do I have to make this run better? Since I have the same design background is there I way I can just hide and show just the controls instead of showing/hiding the entire window?
I have 8 thumbnails on a thumbnail browser page where each thumbnail is just a rectangle from the main image, not the whole thing.
Problem is, this needs to run on some fairly old machines where it's too slow in VB.net although the old VB6 version worked fine. Any obvious ways of speeding the following code up, or do I need to go back to API or use separate thumbnail images?
Private bmp As Bitmap Private bmp2 As Bitmap Private gr As Graphics
My current project is to process several files. The files come from a Unix server and have been SFTP'd to the Windows XP machine. (That's fixed protocol, I don't have control over it.) My problem now is that the Unix new line characters and Windows characters don't match. The solution is to read the file line by line and replace 0x0A with 0x0D + 0x0A, or Asc 10 with Asc 13 + Asc 10, or vbLf with vbCrLf, however you like to say it.Well I have a working function to do this, but any extra speed I could squeeze out of it would be fantastic. The text files I'm working with can reach sizes of about 100MB. So to the question:
Q: What is the fastest way to read a file in, change characters as necessary and then write the file out?Here is my current working code.
Private Sub FormatCharacters(ByVal files As String()) Try For Each fileName As String In files FileSystem.Rename(fileName, fileName & ".old")
I'm working at a new explorer with checkboxes in VB 2005. It's about to be finished.i have pb to get thumbnails in my listview. Usually, com interface used to get thumbnails is IShellItemImageFactory. I had no pb with this one. But i would use IThumbnailCache because i can hold an ID on thumbnails to register them in a ImageList. I wrote IThumbnailCache as follows:
I figured out how to show multiple thumbnail at once with OpenFileDialog and FlowPanelLayout but I want to do it with FolderBrowseDialog - when I select one folder to it show me thumbnails of all images in it.
I'm using this code: Dim OpenFileDialog1 As New OpenFileDialog OpenFileDialog1.Filter = "Images (*.BMP;*.JPG;*.GIF,*.PNG,*.TIFF)|*.BMP;*.JPG;*.GIF;*.PNG;*.TIFF| All files (*.*)|*.*" OpenFileDialog1.Multiselect = True OpenFileDialog1.Title = "Select Photos" [Code] .....
When ListView is not in Virtual mode the following method seems to be the fast method to load a large list into ListView:
Dim items As New List(Of ListViewItem) Dim alllines as String()=System.IO.File.ReadAllLines("FilePath") For each line as string in alllines Dim item As New ListViewItem item.Text = line items.Add(item) Next ListView1.Items.AddRange(items.ToArray())
I have a media gallery type project I'm working on, but I want to enhance it by creating animated thumbnails to "preview" the media. I have already created code to extract 10 incremented images from a pretty much any video format. Now that I have my images, I thought the most efficient way to animate them would be through a GIF. Once you have imported media to a library it will automatically generate the images, and hopefully create the gif thumbnail I'm looking for. How to generate animated GIFs in vb2010?
I have an app that needs to bulk rortate a folder of images either left or right using rotate90flipnone or rotate270flipnone The app does in fact rotate the images but when viewed as thumbnails in explorer they are not rotated. So my app needs to rotate the thumbnail as well.
I am trying to create a photo kiosk software where the user loads images, then they are displayed as thumbnails, and then the user can select a thumbnail (or multiple thumbnails) to choose sizes. (imagine a photo kiosk you would see in walmart for example)
So far I have done the following. I am able to load images. I then dynamically create a panel box for each image, and within the panel box I create a picture box and a label to display the thumbnails and the actual file name.
i want to make a Thumbnails Maker, that makes 20 picture of a video and then a file save dialog will appear when its dune. this is my design i have right now
I have a search function on my company's website (based on .NET 2.0) that allows you to narrow the product catalog using up to 9 different fields. Right now, after you make your selections on the frontend I am building a dynamic query and hitting the database (SQL Server) to get the resulting list of items numbers. I would like to move away from hitting the database everytime and do all of this in memory for faster results. Basically a 3500 - 4500 row "table" with 10 columns: the item number (which could be a primary key) and the 9 attribute fields (which have repeating values for many many rows).
There can be any number of different searches between the 9 columns to get the items you want: Column A = 'foo' AND Column D = 'bar' Column B = 'foo' AND Column C = 'bar' AND Column I = 'me' Column H = 'foo' etc...
Based on my research, the .Select() function seems like the slowest way to perform the search, but it stands out to me as being the quickest and easiest way to perform the narrowing searches to get the list of item numbers: MyDataSet.Select("Column B = 'foo' AND Column E = 'bar' AND Column I = 'me'") In my specific case, what method I use as an alternative that has the same narrowing functionality and better performance instead of settling for the datatable.select() method?
I have a program with three tabs. On tab one I use a folder browser dialogue and load file names into a listbox. These are usually ".tif" image files but could be other image formats. I save the folder location in a variable. On tab 2 I have a Flow Layout Panel. I need to 1) use that folder location on tab 1 as the source of files to be loaded into the flow layout panel and have it do so when I use the Folder Browser Dialogue; 2) I need to click on these tab2 images (in the Flow Layout Panel) to select them, and to trigger events. Mainly create a list of selected image thumbnails.
Document Thumbnails in Navigation Window not working on Print Layout, it only works on Outline and Draft view. It does not allow me to checkmark when in print layout.
Maybe the title isn't very clear on what I try to do, but here's the explanation.
First I use vs 2010 I have a form and a button, the button is to change the form background image.When I click the button I want a popup to appear with 3 or 4 columns of thumbnails to chose from.
I want to display files pretty much as similarly to windows explorer when set to thumbnails as I can. Most importantly I need to be able to show thumbnails of videos and images that windows can(im aware that not all videos are supported).
I'm fairly new at this. I havn't done any programming in years and I've never been amazing at it, I've already got this directory list done so this is the next step in my project...
I am using some code that searches a variable path (usually the entire drive) for images, it then displays the entire path in a listbox. I am able to use a picture box in conjunction to view the pics one at a time. How to display them all in a listview as thumbnails so i can browse them all instead of one at a time using the picturebox. The code I am using returns a array of files if it makes a difference....
What is the best way of quickly loading a datagridview with thumbnails of images and filenames/paths found within a particular folder using a backgroundworker without affecting UI performance ?
While loading, I'd like to continuously filter the dgv's image column through a textbox to display results as the user is typing.
I am writing a program that will read files from a directory and show the thumbnails, then rename the selected files with a time/date stamp and policy number.
I would like to know if the .NET framework gives you a way to retrive the littles thumbnails Windows XP+ generates when you alt+tab. The application I try to make should be able to get a window capture (ALT+PrtScr) of another Window that is not necessary Active and could be partially or completly hidden behind another one. I tried the codes found there [URL] altprintscreen with no success in the case the window I'm trying to capture is not visible.
