PDF or Image can set DPI?

Aspose.PDF Product Family
1

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?

2

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);”>