Debug Blurry Compressed PDF Images — 4 Resolution Checks Before Watermarking

When a compressed PDF appears blurry, debug the embedded image resolution before adjusting compression settings. Preserve the original archival PDF, own the watermark template, and generate a separate derivative for external sharing. Test four critical boundaries: source pixels, placed size, downsampling policy, and final rendered output. Often, geometry reveals the cause of blurriness before any codec does.

First, verify the source image's pixel dimensions and the intended placement size. For example, a 2400-pixel-wide scan placed at 8 inches results in 300 pixels per inch (ppi). If placed at 16 inches, the ppi drops to 150. Geometry is the key to understanding blurriness before any compression codec intervenes.

Next, examine the template owner's behavior. Archive behavior dictates stability in disclosure rules. The best fit lies in maintaining the source file while creating a derivative for external sharing. The main risk lies in accepting the shared template; ownership of the watermarked file should remain in the team that owns the template.

Finally, run four TypeScript preflight tests before watermarking. These tests include inspecting each raster image's dimensions and placement bounds, checking if pixels are below the target ppi, and comparing the results. This four-step TypeScript preflight process ensures reproducibility and assigns clear ownership: the intake path owns source pixels, the template owns placement, the derivative worker handles resampling, and the viewer manages the final preview rendering.