[FFmpeg-devel] [PATCH] ffmpeg: generate more specific error message in case of inconsistent filtering options

[Stefano Sabatini]

In particular, distinguish if the option was -filter or -filter_script.

Suggested-by: Nicolas George
---
 ffmpeg_opt.c | 29 ++++++++++++++---------------
 1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/ffmpeg_opt.c b/ffmpeg_opt.c
index be9b7ed..23b91d9 100644
--- a/ffmpeg_opt.c
+++ b/ffmpeg_opt.c
@@ -1172,10 +1172,10 @@ static void check_streamcopy_filters(OptionsContext *o, AVFormatContext *oc,
 {
     if (ost->filters_script || ost->filters) {
         av_log(NULL, AV_LOG_ERROR,
-               "Filtergraph '%s' or filter_script '%s' was defined for %s output stream "
-               "%d:%d but codec copy was selected.\n",
-               (char *)av_x_if_null(ost->filters, "(none)"),
-               (char *)av_x_if_null(ost->filters_script, "(none)"),
+               "%s '%s' was defined for %s output stream %d:%d but codec copy was selected.\n"
+               "Filtering and streamcopy cannot be used together.\n",
+               ost->filters ? "Filtergraph" : "Filtergraph script",
+               ost->filters ? ost->filters : ost->filters_script,
                av_get_media_type_string(type),
                ost->file_index, ost->index);
         exit_program(1);
@@ -1571,17 +1571,16 @@ static void init_output_filter(OutputFilter *ofilter, OptionsContext *o,
         exit_program(1);
     }
 
-    if (ost->avfilter) {
-        if (ost->filters || ost->filters_script) {
-            av_log(NULL, AV_LOG_ERROR,
-                   "Filter graph '%s' or filter script '%s' was specified through the -filter/-filter_script/-vf/-af option "
-                   "for output stream %d:%d, which is fed from a complex filtergraph.\n"
-                   "-filter/-filter_script and -filter_complex cannot be used together for the same stream.\n",
-                   (char *)av_x_if_null(ost->filters, "(none)"),
-                   (char *)av_x_if_null(ost->filters_script, "(none)"),
-                   ost->file_index, ost->index);
-            exit_program(1);
-        }
+    if (ost->avfilter && (ost->filters || ost->filters_script)) {
+        const char *opt = ost->filters ? "-vf/-af/-filter" : "-filter_script";
+        av_log(NULL, AV_LOG_ERROR,
+               "%s '%s' was specified through the %s option "
+               "for output stream %d:%d, which is fed from a complex filtergraph.\n"
+               "%s and -filter_complex cannot be used together for the same stream.\n",
+               ost->filters ? "Filtergraph" : "Filtergraph script",
+               ost->filters ? ost->filters : ost->filters_script,
+               opt, ost->file_index, ost->index, opt);
+        exit_program(1);
     }
 
     if (configure_output_filter(ofilter->graph, ofilter, ofilter->out_tmp) < 0) {
-- 
1.8.1.2