png

来源： https://stackoverflow.com/questions/31359539/saving-inline-svg-as-a-image-file

来源： https://stackoverflow.com/questions/58805929/issues-adding-multiple-pngs-to-pdf-using-jspdf

来源： https://stackoverflow.com/questions/61355551/how-to-create-and-write-an-indexed-png-image-in-c-or-c

来源： https://stackoverflow.com/questions/63471811/how-to-render-qrimage-as-png-to-be-used-in-a-pdf-document

问题 I am doing image processing in a scientific context. Whenever I need to save an image to the hard drive, I want to be able to reopen it at a later time and get exactly the data that I had before saving it. I exclusively use the PNG format, having always been under the impression that it is a lossless format. Is this always correct, provided I am not using the wrong bit-depth? Should encoder and decoder play no role at all? Specifically, the images I save are present as 2D numpy arrays have

问题 I am doing image processing in a scientific context. Whenever I need to save an image to the hard drive, I want to be able to reopen it at a later time and get exactly the data that I had before saving it. I exclusively use the PNG format, having always been under the impression that it is a lossless format. Is this always correct, provided I am not using the wrong bit-depth? Should encoder and decoder play no role at all? Specifically, the images I save are present as 2D numpy arrays have

问题 I made a "down arrow" in illustrator and saved it as a png with a transparent background. When I put it into my webpage as an img, it shows up in the original color, which is okay. I'm trying to do img:hover{color:red;} and it doesn't work. Does anyone know how to make it work? Thanks 回答1: If you target modern browsers, you may use CSS filters. The hue-rotate filter is suitable for changing colors: filter: hue-rotate(180deg); -webkit-filter: hue-rotate(180deg); The exact amount of degrees

问题 There are 100 PNG images,size=256*256,channel=1 Here is my test code(test for save 2 images in a mat): label = {sprintf('%01d.png\n', 0:100)}; img = regexp(label{:}(1:end-1), '\n', 'split'); F1=im2double(imread(img{1})); F2=im2double(imread(img{2})); label=cat(1,F1,F2);` save('test.mat', 'label') -> The test.mat is 256X256X2 double However,I want to save 100 images in the mat. My idea is F1~100 <=> 1~100.png then cat(1,F1,F2...F100),and save at last. So I try to use eval() in for loop create

问题 I am making a UWP app where i want to pick a user signature scanned by the user and make the picture transparent. now first things first: I am using FileOpenPicker to pick the storage file. Work tried by me public async void Button_AddSign_Click(object sender, RoutedEventArgs e) { try { var _filePicker = new FileOpenPicker(); _filePicker.SuggestedStartLocation = PickerLocationId.Desktop; _filePicker.ViewMode = PickerViewMode.Thumbnail; _filePicker.FileTypeFilter.Add(".png"); IStorageFile

问题 I am encoding my images in Base64 before uploading them to the server. I need to get their file sizes down to a specific size (500kB). I have tried to get the ratio between the original and the desired file size and reducing de height and width accordingly. But it does not work. Any help? 回答1: Some other users had the same question. Maybe this helps you: JavaScript reduce the size and quality of image with based64 encoded code As far as i'm concerned, there is no way to reduce the filesize of