avutil/channel_layout: add specific text versions for unknown and unused channels

Signed-off-by: Marton Balint <cus@passwd.hu>

libavutil/channel_layout.c

@@ -86,6 +86,10 @@ void av_channel_name_bprint(AVBPrint *bp, enum AVChannel channel_id)
         av_bprintf(bp, "%s", channel_names[channel_id].name);
     else if (channel_id == AV_CHAN_NONE)
         av_bprintf(bp, "NONE");
+    else if (channel_id == AV_CHAN_UNKNOWN)
+        av_bprintf(bp, "UNK");
+    else if (channel_id == AV_CHAN_UNUSED)
+        av_bprintf(bp, "UNSD");
     else
         av_bprintf(bp, "USR%d", channel_id);
 }
@@ -115,6 +119,10 @@ void av_channel_description_bprint(AVBPrint *bp, enum AVChannel channel_id)
         av_bprintf(bp, "%s", channel_names[channel_id].description);
     else if (channel_id == AV_CHAN_NONE)
         av_bprintf(bp, "none");
+    else if (channel_id == AV_CHAN_UNKNOWN)
+        av_bprintf(bp, "unknown");
+    else if (channel_id == AV_CHAN_UNUSED)
+        av_bprintf(bp, "unused");
     else
         av_bprintf(bp, "user %d", channel_id);
 }
@@ -151,6 +159,11 @@ enum AVChannel av_channel_from_string(const char *str)
         if (channel_names[i].name && !strcmp(str, channel_names[i].name))
             return i;
     }
+    if (!strcmp(str, "UNK"))
+        return AV_CHAN_UNKNOWN;
+    if (!strcmp(str, "UNSD"))
+        return AV_CHAN_UNUSED;
+
     if (!strncmp(str, "USR", 3)) {
         const char *p = str + 3;
         id = strtol(p, &endptr, 0);

libavutil/tests/channel_layout.c

@@ -348,6 +348,8 @@ int main(void)
     CHANNEL_LAYOUT_FROM_STRING("Dummy@FL");
     CHANNEL_LAYOUT_FROM_STRING("FR+Dummy");
     CHANNEL_LAYOUT_FROM_STRING("FR+Dummy@FL");
+    CHANNEL_LAYOUT_FROM_STRING("UNK+UNSD");
+    CHANNEL_LAYOUT_FROM_STRING("NONE");
     CHANNEL_LAYOUT_FROM_STRING("FR+@FL");
     CHANNEL_LAYOUT_FROM_STRING("FL+@");
     CHANNEL_LAYOUT_FROM_STRING("FR+FL@Foo+USR63@Foo");

tests/ref/fate/channel_layout

@@ -148,6 +148,8 @@ With "Dummy":                                                        fail
 With "Dummy@FL":                                                     fail
 With "FR+Dummy":                                                     fail
 With "FR+Dummy@FL":                                                  fail
+With "UNK+UNSD":                                    2 channels (UNK+UNSD)
+With "NONE":                                                         fail
 With "FR+@FL":                                                       fail
 With "FL+@":                                                         fail
 With "FR+FL@Foo+USR63@Foo":              3 channels (FR+FL@Foo+USR63@Foo)
@@ -236,5 +238,5 @@ With "ambisonic 2+stereo": AMBI   (ambisonic 2+stereo)
 With "2C": UNSPEC (2 channels)
   == UNSPEC (2 channels)
   != NATIVE
-  == CUSTOM (2 channels (USR768+USR768))
+  == CUSTOM (2 channels (UNK+UNK))
   != AMBI