[FFmpeg-user] Weird characters in created passlogfile on Windows

[Thierry Lelégard]

Hello,

I found a strange problem with ffmpeg on Windows (not tested yet on Linux)
with the -passlogfile option.

Consider a file path containing non ASCII characters like è (e grave) used
in all file specifications (in a directory name for instance). There are
three different use cases: input file, output file, pass log file.

In the first two cases, the non-ASCII characters in file names are processed
correctly. But in the case of the pass log file, the file name is transformed
into some weird sequence (typical UTF-8 sequence). The strange thing is that
ffmpeg creates two files, the pass log file and the output file, but processes
the characters in the file name quite differently. The way the two files are
created must be completely different.

See the following example:

D:\Public\Videos\TEMP>ls -l h*
-rw-rw-rw-   1 user     group    18800000 Oct 15 22:50 hè.ts

There is one single file. Let's transcode it that way;

D:\Public\Videos\TEMP>ffmpeg -i hè.ts -pass 1 -passlogfile hè hè.mpg
ffmpeg version N-56060-gbcd1c20 Copyright (c) 2000-2013 the FFmpeg developers
   built on Sep  6 2013 00:49:05 with gcc 4.7.3 (GCC)
   configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetype 
--enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex 
--enable-libtheora --enable-libtwolame --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
   libavutil      52. 43.100 / 52. 43.100
   libavcodec     55. 31.101 / 55. 31.101
   libavformat    55. 16.101 / 55. 16.101
   libavdevice    55.  3.100 / 55.  3.100
   libavfilter     3. 83.104 /  3. 83.104
   libswscale      2.  5.100 /  2.  5.100
   libswresample   0. 17.103 /  0. 17.103
   libpostproc    52.  3.100 / 52.  3.100
[....]

Now look at the result:

D:\Public\Videos\TEMP>ls -l h*
-rw-rw-rw-   1 user     group      258179 Oct 15 22:50 hè-0.log
-rw-rw-rw-   1 user     group     5261312 Oct 15 22:50 hè.mpg
-rw-rw-rw-   1 user     group    18800000 Oct 15 22:50 hè.ts

The command contains "-passlogfile hè hè.mpg" but the "hè" in the two
created files resulted in two different encodings.

The problem is that the specified file name on the command line does NOT
correspond to the actual file name in the file system. One may say that
we don't care since this is a temporary log file.

But there is a real problem when the non-ASCII character is in the name
of the directory for all files. In that case, ffmpeg transforms the
directory name and the resulting path is invalid since the transformed
path uses a non-existent directory.

Error resulting from option -passlogfile D:\Public\Videos\DVD\hè\fflog
(assuming that the directory D:\Public\Videos\DVD\hè does exist and
contains all files);

Cannot write log file 'D:\Public\Videos\DVD\hè\fflog-0.log' for pass-1 encoding: No such file or directory

Interestingly, the characters in the error message are correct. So, you do
not understand why this failed. This is only after a test with an accent
in the file name but none in the directory name that I discovered the
transformation.

Is this known? Shall I open a bug report for that?

Best regards,
-Thierry