[FFmpeg-devel] [PATCH] avformat: add dump_metadata_lines

[Michael Niedermayer]

TODO: bump version, update APIChanges

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
---
 libavformat/avformat.h      |    8 ++++++++
 libavformat/dump.c          |   24 ++++++++++++++++++------
 libavformat/options_table.h |    1 +
 3 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 2e54ed1..cbe3608 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -1616,6 +1616,14 @@ typedef struct AVFormatContext {
      */
     char *format_whitelist;
 
+    /**
+     * Maximum number of lines per metadata tag to dump with av_log.
+     * -1 means default
+     * - encoding: unused
+     * - decoding: set by user through AVOptions (NO direct access)
+     */
+    int dump_metadata_lines;
+
     /*****************************************************************
      * All fields below this line are not part of the public API. They
      * may not be used outside of libavformat and can be changed and
diff --git a/libavformat/dump.c b/libavformat/dump.c
index 56b37ff..38286b8 100644
--- a/libavformat/dump.c
+++ b/libavformat/dump.c
@@ -126,7 +126,7 @@ static void print_fps(double d, const char *postfix)
         av_log(NULL, AV_LOG_INFO, "%1.0fk %s", d / 1000, postfix);
 }
 
-static void dump_metadata(void *ctx, AVDictionary *m, const char *indent)
+static void dump_metadata(void *ctx, AVDictionary *m, const char *indent, int dump_metadata_lines_arg)
 {
     if (m && !(av_dict_count(m) == 1 && av_dict_get(m, "language", NULL, 0))) {
         AVDictionaryEntry *tag = NULL;
@@ -135,16 +135,28 @@ static void dump_metadata(void *ctx, AVDictionary *m, const char *indent)
         while ((tag = av_dict_get(m, "", tag, AV_DICT_IGNORE_SUFFIX)))
             if (strcmp("language", tag->key)) {
                 const char *p = tag->value;
+                int lines = 0;
+                int dump_metadata_lines = dump_metadata_lines_arg;
+                if (dump_metadata_lines == -1) {
+                    dump_metadata_lines = strcmp("comment", tag->key) ? 1 : 25;
+                }
                 av_log(ctx, AV_LOG_INFO,
                        "%s  %-16s: ", indent, tag->key);
                 while (*p) {
                     char tmp[256];
                     size_t len = strcspn(p, "\x8\xa\xb\xc\xd");
+                    if (lines >= dump_metadata_lines) {
+                        av_log(ctx, AV_LOG_INFO, "[%"SIZE_SPECIFIER" bytes ommited, use \'-dump_metadata_lines <max>\' to see more]", strlen(p));
+                        break;
+                    }
                     av_strlcpy(tmp, p, FFMIN(sizeof(tmp), len+1));
                     av_log(ctx, AV_LOG_INFO, "%s", tmp);
                     p += len;
                     if (*p == 0xd) av_log(ctx, AV_LOG_INFO, " ");
-                    if (*p == 0xa) av_log(ctx, AV_LOG_INFO, "\n%s  %-16s: ", indent, "");
+                    if (*p == 0xa) {
+                        av_log(ctx, AV_LOG_INFO, "\n%s  %-16s: ", indent, "");
+                        lines++;
+                    }
                     if (*p) p++;
                 }
                 av_log(ctx, AV_LOG_INFO, "\n");
@@ -420,7 +432,7 @@ static void dump_stream_format(AVFormatContext *ic, int i,
         av_log(NULL, AV_LOG_INFO, " (clean effects)");
     av_log(NULL, AV_LOG_INFO, "\n");
 
-    dump_metadata(NULL, st->metadata, "    ");
+    dump_metadata(NULL, st->metadata, "    ", ic->dump_metadata_lines);
 
     dump_sidedata(NULL, st, "    ");
 }
@@ -438,7 +450,7 @@ void av_dump_format(AVFormatContext *ic, int index,
            index,
            is_output ? ic->oformat->name : ic->iformat->name,
            is_output ? "to" : "from", url);
-    dump_metadata(NULL, ic->metadata, "  ");
+    dump_metadata(NULL, ic->metadata, "  ", ic->dump_metadata_lines);
 
     if (!is_output) {
         av_log(NULL, AV_LOG_INFO, "  Duration: ");
@@ -480,7 +492,7 @@ void av_dump_format(AVFormatContext *ic, int index,
         av_log(NULL, AV_LOG_INFO,
                "end %f\n", ch->end * av_q2d(ch->time_base));
 
-        dump_metadata(NULL, ch->metadata, "    ");
+        dump_metadata(NULL, ch->metadata, "    ", ic->dump_metadata_lines);
     }
 
     if (ic->nb_programs) {
@@ -490,7 +502,7 @@ void av_dump_format(AVFormatContext *ic, int index,
                                                   "name", NULL, 0);
             av_log(NULL, AV_LOG_INFO, "  Program %d %s\n", ic->programs[j]->id,
                    name ? name->value : "");
-            dump_metadata(NULL, ic->programs[j]->metadata, "    ");
+            dump_metadata(NULL, ic->programs[j]->metadata, "    ", ic->dump_metadata_lines);
             for (k = 0; k < ic->programs[j]->nb_stream_indexes; k++) {
                 dump_stream_format(ic, ic->programs[j]->stream_index[k],
                                    index, is_output);
diff --git a/libavformat/options_table.h b/libavformat/options_table.h
index 40f1e0a..75ddf9c 100644
--- a/libavformat/options_table.h
+++ b/libavformat/options_table.h
@@ -99,6 +99,7 @@ static const AVOption avformat_options[] = {
 {"dump_separator", "set information dump field separator", OFFSET(dump_separator), AV_OPT_TYPE_STRING, {.str = ", "}, CHAR_MIN, CHAR_MAX, D|E},
 {"codec_whitelist", "List of decoders that are allowed to be used", OFFSET(codec_whitelist), AV_OPT_TYPE_STRING, { .str = NULL },  CHAR_MIN, CHAR_MAX, D },
 {"format_whitelist", "List of demuxers that are allowed to be used", OFFSET(format_whitelist), AV_OPT_TYPE_STRING, { .str = NULL },  CHAR_MIN, CHAR_MAX, D },
+{"dump_metadata_lines", "Maximum number of lines per metadata tag to dump with av_log", OFFSET(dump_metadata_lines), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, D },
 {NULL},
 };
 
-- 
1.7.9.5