lavf/segment: deprecate "ext" format in favor of "csv"

The new option name is more descriptive.

doc/muxers.texi

@@ -490,9 +490,9 @@ The following values are recognized:
 @item flat
 Generate a flat list for the created segments, one segment per line.
 
-@item ext
+@item csv, ext
 Generate a list for the created segments, one segment per line,
-each line matching the format:
+each line matching the format (comma-separated values):
 @example
 @var{segment_filename},@var{segment_start_time},@var{segment_end_time}
 @end example
@@ -504,7 +504,11 @@ RFC4180) is applied if required.
 @var{segment_start_time} and @var{segment_end_time} specify
 the segment start and end time expressed in seconds.
 
-A list file with the suffix @code{".ext"} will auto-select this format.
+A list file with the suffix @code{".csv"} or @code{".ext"} will
+auto-select this format.
+
+@code{ext} is deprecated in favor or @code{csv}.
+
 @item m3u8
 Generate an extended M3U8 file, version 4, compliant with
 @url{http://tools.ietf.org/id/draft-pantos-http-live-streaming-08.txt}.
@@ -559,7 +563,7 @@ ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.list out%03d.nu
 As the example above, but segment the input file according to the split
 points specified by the @var{segment_times} option:
 @example
-ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.ext -segment_times 1,2,3,5,8,13,21 out%03d.nut
+ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 out%03d.nut
 @end example
 
 @item
@@ -569,7 +573,7 @@ with the segment option @var{segment_time_delta} to account for
 possible roundings operated when setting key frame times.
 @example
 ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -vcodec mpeg4 -acodec pcm_s16le -map 0 \
--f segment -segment_list out.ext -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
+-f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
 @end example
 In order to force key frames on the input file, transcoding is
 required.

libavformat/segment.c

@@ -39,11 +39,13 @@
 typedef enum {
     LIST_TYPE_UNDEFINED = -1,
     LIST_TYPE_FLAT = 0,
-    LIST_TYPE_EXT,
+    LIST_TYPE_CSV,
     LIST_TYPE_M3U8,
     LIST_TYPE_NB,
 } ListType;
 
+#define LIST_TYPE_EXT LIST_TYPE_CSV
+
 typedef struct {
     const AVClass *class;  /**< Class for private options. */
     int segment_idx;       ///< index of the segment file to write, starting from 0
@@ -310,13 +312,16 @@ static int seg_write_header(AVFormatContext *s)
 
     if (seg->list) {
         if (seg->list_type == LIST_TYPE_UNDEFINED) {
-            if      (av_match_ext(seg->list, "ext" )) seg->list_type = LIST_TYPE_EXT;
+            if      (av_match_ext(seg->list, "csv" )) seg->list_type = LIST_TYPE_CSV;
+            else if (av_match_ext(seg->list, "ext" )) seg->list_type = LIST_TYPE_EXT;
             else if (av_match_ext(seg->list, "m3u8")) seg->list_type = LIST_TYPE_M3U8;
             else                                      seg->list_type = LIST_TYPE_FLAT;
         }
         if ((ret = segment_list_open(s)) < 0)
             goto fail;
     }
+    if (seg->list_type == LIST_TYPE_EXT)
+        av_log(s, AV_LOG_WARNING, "'ext' list type option is deprecated in favor of 'csv'\n");
 
     for (i = 0; i< s->nb_streams; i++)
         seg->has_video +=
@@ -445,6 +450,7 @@ static const AVOption options[] = {
     { "segment_list_size", "set the maximum number of playlist entries", OFFSET(list_size), AV_OPT_TYPE_INT,  {.dbl = 0},     0, INT_MAX, E },
     { "segment_list_type", "set the segment list type",                  OFFSET(list_type), AV_OPT_TYPE_INT,  {.dbl = LIST_TYPE_UNDEFINED}, -1, LIST_TYPE_NB-1, E, "list_type" },
     { "flat", "flat format",     0, AV_OPT_TYPE_CONST, {.dbl=LIST_TYPE_FLAT }, INT_MIN, INT_MAX, 0, "list_type" },
+    { "csv",  "csv format",      0, AV_OPT_TYPE_CONST, {.dbl=LIST_TYPE_CSV  }, INT_MIN, INT_MAX, 0, "list_type" },
     { "ext",  "extended format", 0, AV_OPT_TYPE_CONST, {.dbl=LIST_TYPE_EXT  }, INT_MIN, INT_MAX, 0, "list_type" },
     { "m3u8", "M3U8 format",     0, AV_OPT_TYPE_CONST, {.dbl=LIST_TYPE_M3U8 }, INT_MIN, INT_MAX, 0, "list_type" },
     { "segment_time",      "set segment duration",                       OFFSET(time_str),AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       E },