Rename map_metadata into metadata.map, add metadata.deduplicate, make…

… sure crossfade transition sources do no re-send old source metadata.

Fixes: #2153

CHANGES.md

@@ -15,6 +15,8 @@ Changed:
 * Optimized memory usage when accessing ground terms.
 * Allow crossfade duration getter to override duration at the
   end of each track if duration isn't set via metadata.
+* Make sure crossfade metadata are not duplicated (#2153)
+* Renamed `map_metadata` into `metadata.map`, deprecated `map_metadata`.
 * Enhanced remaining time when using `add` (#2255)
 
 Fixed:

doc/content/cookbook.md

@@ -413,7 +413,7 @@ def source_tag(s,tag) =
   def f(_)
     [("source_tag",(tag:string))]
   end
-  map_metadata(id=tag,insert_missing=true,f,s)
+  metadata.map(id=tag,insert_missing=true,f,s)
 end
 
 # Tag our sources

doc/content/metadata.md

@@ -43,7 +43,7 @@ def append_title(m) =
 end
 
 # Apply map_metadata to s using append_title
-s = map_metadata(append_title, s)
+s = metadata.map(append_title, s)
 ```
 
 The effect of `map_metadata` by default is to update the metadata with the

doc/content/migrating.md

@@ -224,6 +224,7 @@ deprecated operatords. Here's a list of the most important ones:
 * `empty` is replaced by: `source.fail`
 * `file.unlink` is replaced by: `file.remove`
 * `string.utf8.escape` is replaced by: `string.escape`   
+* `map_metadata` is replaced by: `metadata.map`
 
 ### Windows build
 

doc/content/on2_part2.md

@@ -247,7 +247,7 @@ end
 Finally, we apply `map_metadata` to the source, just after the `request.dynamic.list`
 definition in `radio.liq`:
 ```liquidsoap
-s = map_metadata(update_title,s)
+s = metadata.map(update_title,s)
 ```
 
 Solutions:
@@ -436,7 +436,7 @@ end
 ```
 And, we add the following line in `radio.liq` after the `request.dynamic.list` line:
 ```liquidsoap
-s = map_metadata(add_replaygain,s)
+s = metadata.map(add_replaygain,s)
 ```
 Finally, we add the `amplify` operator. We set the default amplification
 to `1.`, i.e. no amplification, and tell the operator to update this value with

libs/deprecations.liq

@@ -95,10 +95,17 @@ def playlist.once(~id=null(),~random=false,~reload_mode="",
   playlist(reload_mode=reload_mode, loop=false, id=id, mode=mode, prefetch=prefetch, check_next=filter, uri)
 end
 
-# Deprecated: this function has been replaced by `map_metadata`.
+# Deprecated: use metadata.map
+# @flag deprecated
+def map_metadata(%argsof(metadata.map), fn, (s:source))
+  deprecated("map_metadata", "metadata.map")
+  metadata.map(%argsof(metadata.map), fn, s)
+end
+
+# Deprecated: this function has been replaced by `metadata.map`.
 # @flag deprecated
 def rewrite_metadata(l,~insert_missing=true,~update=true,~strip=false,s)
-  deprecated("rewrite_metadata", "map_metadata")
+  deprecated("rewrite_metadata", "metadata.map")
   def map(m)
     def apply(x)
       label = fst(x)
@@ -107,7 +114,7 @@ def rewrite_metadata(l,~insert_missing=true,~update=true,~strip=false,s)
     end
     list.map(apply,l)
   end
-  map_metadata(map,insert_missing=insert_missing,update=update,strip=strip,s)
+  metadata.map(map,insert_missing=insert_missing,update=update,strip=strip,s)
 end
 
 # Deprecated: this function will be removed in a future release

libs/fades.liq

@@ -357,11 +357,13 @@ end
 # @param ~medium       Smart crossfade: value, in dB, for medium sound level.
 # @param ~margin       Smart crossfade: margin to detect sources that have too different \
 #                      sound level for crossing.
+# @param ~deduplicate  Crossfade transitions can generate duplicate metadata. When `true`, the operator \
+#                      removes duplicate metadata from the returned source.
 # @param s             The input source.
 def crossfade(~id=null(), ~duration=5.,~override_duration="liq_cross_duration",
               ~fade_in=3.,~fade_out=3.,~smart=false,
               ~default=(fun (a,b) -> (sequence([a, b]):source)),
-              ~high=-15., ~medium=-32., ~margin=4.,
+              ~high=-15., ~medium=-32., ~margin=4., ~deduplicate=true,
               ~minimum=(-1.),~width=2.,~conservative=true,s)
   id = string.id.default(default="crossfade", id)
   log = log(label=id)
@@ -389,8 +391,16 @@ def crossfade(~id=null(), ~duration=5.,~override_duration="liq_cross_duration",
       simple_transition
     end
 
-  cross(id=id, width=width, duration=duration, override_duration=override_duration,
-        conservative=conservative, minimum=minimum, transition, s)
+  let (cross_id, deduplicate_id) = deduplicate ? (null(), null(id)) : (null(id), null())
+
+  s = cross(id=cross_id, width=width, duration=duration, override_duration=override_duration,
+            conservative=conservative, minimum=minimum, transition, s)
+
+  if deduplicate then
+    metadata.deduplicate(id=deduplicate_id, s)
+  else
+    s
+  end
 end
 
 # Mixes two streams, with faded transitions between the state when only the

libs/metadata.liq

@@ -163,3 +163,20 @@ def metadata.json.parse(s) =
   m = json.parse(default=[("invalid","invalid")], s)
   if m == [("invalid","invalid")] then [] else m end
 end
+
+# Remove duplicate metadata in source
+# @category Source / Track Processing
+# @param ~id Source id
+# @param s source
+def metadata.deduplicate(~id=null("metadata.deduplicate"), s) =
+  last_meta = ref([])
+  def f(m) =
+    if m == !last_meta then
+      []
+    else
+      last_meta := m
+      m
+    end
+  end
+  metadata.map(id=id, insert_missing=false, update=false, strip=true, f, s)
+end

libs/shoutcast.liq

@@ -27,7 +27,7 @@ def output.shoutcast(
       m
     end
   end
-  s = map_metadata(map,s)
+  s = metadata.map(map,s)
 
   output.icecast(
     %argsof(

libs/source.liq

@@ -26,7 +26,7 @@ end
 # Removes all metadata coming from a source.
 # @category Source / Track Processing
 def drop_metadata(s)
-  map_metadata(fun(_)->[],update=false,strip=true,insert_missing=false,s)
+  metadata.map(fun(_)->[],update=false,strip=true,insert_missing=false,s)
 end
 
 # Creates a source that plays only one track of the input source.

src/operators/map_metadata.ml

@@ -24,7 +24,7 @@ open Source
 
 class map_metadata ~kind source rewrite_f insert_missing update strip =
   object (self)
-    inherit operator ~name:"map_metadata" kind [source]
+    inherit operator ~name:"metadata.map" kind [source]
     method stype = source#stype
     method is_ready = source#is_ready
     method remaining = source#remaining
@@ -69,7 +69,7 @@ class map_metadata ~kind source rewrite_f insert_missing update strip =
 let register =
   let kind = Lang.any in
   let return_t = Lang.kind_type_of_kind_format kind in
-  Lang.add_operator "map_metadata"
+  Lang.add_operator "metadata.map"
     [
       ( "",
         Lang.fun_t

tests/regression/AC5109.liq

@@ -12,10 +12,10 @@ s = sequence([s1,s2])
 
 def transition(a, b) =
   s1 = sine(duration=0.5)
-  s1 = map_metadata(fun (_) -> [("type", "s1")], s1)
+  s1 = metadata.map(fun (_) -> [("type", "s1")], s1)
 
   s2 = sine(duration=0.5)
-  s2 = map_metadata(fun (_) -> [("type", "s2")], s2)
+  s2 = metadata.map(fun (_) -> [("type", "s2")], s2)
   sequence([(a.source:source), (s1:source), (s2:source), (b.source:source)])
 end
 

tests/regression/GH1129.liq

@@ -15,7 +15,7 @@ def m1(_) =
   [("id","s1")]
 end
 
-s1 = map_metadata(id="s1",m1,s1)
+s1 = metadata.map(id="s1",m1,s1)
 
 s2_ready = ref(false)
 
@@ -25,15 +25,15 @@ def m2(_) =
   [("id","s2")]
 end
 
-s2 = map_metadata(id="s2",m2,s2)
+s2 = metadata.map(id="s2",m2,s2)
 
 s3 = blank(id="s3",duration=0.04)
 
 def m3(_) =
   [("id","s3")]
 end
 
-s3 = map_metadata(id="s3",m3,s3)
+s3 = metadata.map(id="s3",m3,s3)
 
 def f(m) =
   s2_ready := !s2_ready or m["id"] == "s3"

tests/regression/GH1279.liq

@@ -10,15 +10,15 @@ def m1(_) =
   [("id","s1")]
 end
 
-s1 = map_metadata(id="s1",m1,s1)
+s1 = metadata.map(id="s1",m1,s1)
 
 s2 = blank(duration=0.04)
 
 def m2(_) =
   [("id","s2")]
 end
 
-s2 = map_metadata(id="s2",m2,s2)
+s2 = metadata.map(id="s2",m2,s2)
 
 def f(m) =
   selected := list.add(m["id"],!selected)

tests/regression/GH1327.liq

@@ -12,15 +12,15 @@ def m1(_) =
   [("id","s1")]
 end
 
-s1 = map_metadata(id="s1",m1,s1)
+s1 = metadata.map(id="s1",m1,s1)
 
 s2 = blank(duration=0.1)
 
 def m2(_) =
   [("id","s2")]
 end
 
-s2 = map_metadata(id="s2",m2,s2)
+s2 = metadata.map(id="s2",m2,s2)
 
 def f(m) =
   selected := list.add(m["id"],!selected)
@@ -34,7 +34,7 @@ def m_noise(_) =
   [("id","noise")]
 end
 
-noise = map_metadata(id="noise", m_noise, noise())
+noise = metadata.map(id="noise", m_noise, noise())
 
 ready = ref(false)
 

tests/streams/cross.liq

@@ -5,23 +5,44 @@
 video.frame.rate.set(24)
 
 a = sine(duration=5.,440.)
-b = sine(880.)
+a = metadata.map(update=false, (fun (_) -> [("title","a")]), a)
+
+b = sine(duration=5.,880.)
+b = metadata.map(update=false, (fun (_) -> [("title","b")]), b)
+
 s = sequence([a,b])
 
 def t(a, b)
   log.important("Crossing!")
   log.important("Levels: #{a.db_level} / #{b.db_level}")
   log.important("Metadata: #{a.metadata} / #{b.metadata}")
-  add(normalize=false, [a.source, b.source])
+  sequence([a.source, b.source])
 end
 
 s = cross(duration=3., width=1., t, s)
 
-output.dummy(fallible=true, s)
+seen_a = ref(false)
+seen_b = ref(false)
+
+def check_duplicate(m) =
+  if m["title"] == "a" then
+    if !seen_a then test.fail() else seen_a := true end
+  end
+  if m["title"] == "b" then
+    if !seen_b then test.fail() else seen_b := true end
+  end
+end
+
+s.on_metadata(check_duplicate)
+
+clock.assign_new(sync="none",[s])
 
-def on_done () =
-  test.pass()
-  shutdown()
+def on_stop () =
+  if !seen_a and !seen_b then
+    test.pass()
+  else
+    test.fail()
+  end
 end
 
-thread.run(delay=8., on_done)
+output.dummy(fallible=true, on_stop=on_stop,s)

tests/streams/crossfade.liq

@@ -4,16 +4,58 @@
 
 video.frame.rate.set(24)
 
-a = sine(duration=5., 440.)
-b = sine(880.)
+a = sine(duration=20.,440.)
+a = metadata.map(update=false, (fun (_) -> [("title","a1")]), a)
+
+b = sine(duration=20.,880.)
+b = metadata.map(update=false, (fun (_) -> [("title","b1")]), b)
+
+s = sequence([a,b])
+
+fa = crossfade(smart=true, deduplicate=true, s)
+
+a = sine(duration=20.,440.)
+a = metadata.map(update=false, (fun (_) -> [("title","a2")]), a)
+
+b = sine(duration=20.,880.)
+b = metadata.map(update=false, (fun (_) -> [("title","b2")]), b)
+
 s = sequence([a,b])
-s = crossfade(duration=3., s)
 
-output.dummy(fallible=true, s)
+fb = crossfade(smart=true, deduplicate=false, s)
+
+s = sequence([merge_tracks(fa), fb])
+
+dedup_a = ref(0)
+dedup_b = ref(0)
+dup_a = ref(0)
+dup_b = ref(0)
+
+def check_duplicate(m) =
+  if m["title"] == "a1" then
+    dedup_a := !dedup_a + 1
+  end
+  if m["title"] == "b1" then
+    dedup_b := !dedup_b + 1
+  end
+  if m["title"] == "a2" then
+    dup_a := !dup_a + 1
+  end
+  if m["title"] == "b2" then
+    dup_b := !dup_b + 1
+  end
+end
+
+s.on_metadata(check_duplicate)
+
+clock.assign_new(sync="none",[s])
 
-def on_done () =
-  test.pass()
-  shutdown()
+def on_stop () =
+  if !dup_a == 2 and !dup_b == 2 and !dedup_a == 1 and !dedup_b == 1 then
+    test.pass()
+  else
+    test.fail()
+  end
 end
 
-thread.run(delay=8., on_done)
+output.dummy(fallible=true, on_stop=on_stop,s)

tests/streams/random.liq

@@ -15,7 +15,7 @@ def m1(_) =
   [("id","s1")]
 end
 
-s1 = map_metadata(m1,s1)
+s1 = metadata.map(m1,s1)
 
 s1_ready = ref(true)
 
@@ -29,7 +29,7 @@ def m2(_) =
   [("id","s2")]
 end
 
-s2 = map_metadata(id="s2",m2,s2)
+s2 = metadata.map(id="s2",m2,s2)
 
 s2_ready = ref(false)