None value for PNG filters

[omkar-mohanty]

While executing the read.rs example, I tried to extract images from a pdf with PNG images in it. The raw_image_data function returned None for filter , but shouldn't the correct returned filter be a FlateDecode ?

[s3bk]

Sounds about right.

Could you adjust

pdf/pdf/src/object/types.rs

Line 557 in a6e2abc

pub fn raw_image_data(&self, resolve: &impl Resolve) -> Result<(Arc<[u8]>, Option<&StreamFilter>)> {

accordingly and make a PR?

[omkar-mohanty]

Sure 👍 . I had a question though does using the raw_image_data on a PNG image return the IDAT chunk?

[s3bk]

I don't think so. So you may have to do some reconstruction, and possibly add a as_png method that does this.