On 26/02/17 11:45, Nicolas George wrote: > L'octidi 8 ventôse, an CCXXV, Mark Thompson a écrit : >> I suspect that the thing I am doing seriously wrong is attempting to >> use an opaque proprietary library which has more complex semantics >> than we can sensibly express. > > Nothing like that. It is only your take on error messages that seems > wrong to me. > >>> If the error results from invalid parameters set by the user, then the >>> error message should say so, possibly stating what parameter and its >>> acceptable values. >> For this sort of thing the set of acceptable inputs is not >> well-defined, unfortunately. > > Please be careful, you replied to the anecdotal part of my paragraph and > completely neglected its core.
No; the point was that we are unable to determine whether the error resulted from invalid parameters set by the user. >> Would you prefer something like "external error: >> MFXVideoVPP_RunFrameVPPAsync returned error code %d", which would >> emphasise the origin of the problem? > > No, it is even worse. > > Try to put yourself in the shoes of a completely clueless user: does > this error message tell you anything useful at all? It at least offers some direction for where to go looking for the problem. What form would you suggest the message takes? > To get more relevant advice, I believe you need to explain, here and > now, what causes the error: user settings, system/hardware, or bug. Yes, I suppose it must be one of those. I'm not sure offering the possibilities to the user is helpful, though. (The -16 (MFX_ERR_UNDEFINED_BEHAVIOUR) that I get is not documented as a valid return value from the function <https://software.intel.com/en-us/node/628434#MFXVideoVPP1>, so it is difficult to read anything into it.) _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
