Any picture can be saved as PDF document, the tricky part is to find at least a viewer with printing capability in order to do so. XnView for example is excellent viewer that supports hundreds of picture formats and ideal choice for this type of conversion. It should support .ecw pictures well enough and can save them as PDF documents.
Convert Enhanced Compressed Wavelet image format to Adobe Portable document format.
We have found 2 software records in our database eligible for .ecw to .pdf file format conversion.
Microsoft Windows software - convert ecw to pdf on Windows
A drawing software used to create technical illustrations and graphics
Convert from ecw file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned ecw to pdf. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Multiplatform software - convert ecw to pdf on any platform
A popular utility for viewing and converting graphic files