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PDF or Image can set DPI?

I have one quesiton, I want to use aspose.pdf to do image convert to pdf, my question is that if I can set DPI by using aspose.pdf or I can use aspose.image to set DPI before convert to pdf? I also want to do image lossless transformation, any suggestions or guidance on it?

Hi,


Thank you for contacting support. Please try the following code which shows how to get an image with certain resolution from a PDF file and then replace it using Aspose.Pdf for .NET API.

[.NET, C#]
<span class=“rem” style=“color: rgb(0, 128, 0); font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre;”>// Internal image resolution change<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
Document document = <span class=“kwrd” style=“color: rgb(0, 0, 255); font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre;”>new<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”> Document(myDir + “image.pdf”);<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
XImageCollection images = document.Pages[1].Resources.Images;<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
MemoryStream baos = <span class=“kwrd” style=“color: rgb(0, 0, 255); font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre;”>new<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”> MemoryStream();<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
<span class=“rem” style=“color: rgb(0, 128, 0); font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre;”>// define resolution<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
images[1].Save(baos, 10);<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
<br style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre;”><span class=“rem” style=“color: rgb(0, 128, 0); font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre;”>// Replace a particular image<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
document.Pages[1].Resources.Images.Replace(1, baos);<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
<span class=“rem” style=“color: rgb(0, 128, 0); font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre;”>// save PDF<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>
document.Save(myDir + “imageWithNewResolution.pdf”);
<span style=“font-family: “Courier New”, Consolas, Courier, monospace; font-size: small; white-space: pre; background-color: rgb(255, 255, 255);”>