How to make quality of PDF thumbnail image better ?

[kso0653]

I want to make quality of PDF thumbnail image better. (pdf -> jpg)

Please let me know 🙏

that is part of my cantaloupe.properties

processor.ManualSelectionStrategy.pdf = PdfBoxProcessor
processor.stream_retrieval_strategy = StreamStrategy
processor.fallback_retrieval_strategy = DownloadStrategy
processor.dpi = 200
processor.background_color = white
processor.downscale_filter = bicubic
processor.upscale_filter = bicubic
processor.downscale_linear = false
processor.sharpen = 0
processor.jpg.progressive = true
processor.jpg.quality = 100
processor.tif.compression = LZW
processor.pdf.scratch_file_enabled = false
processor.pdf.max_memory_bytes = -1