vp8enc: provide support for multiple pass cache files

Some files may provide different caps insight of one stream. Since vp8enc
support caps reinit, we should support cache reinit too.
If more then file cache file will be created, the naming will be:
cache
cache.1
cache.2
...

https://bugzilla.gnome.org/show_bug.cgi?id=747728

ext/vpx/gstvp8enc.c

@@ -557,7 +557,9 @@ gst_vp8_enc_class_init (GstVP8EncClass * klass)
 
   g_object_class_install_property (gobject_class, PROP_MULTIPASS_CACHE_FILE,
       g_param_spec_string ("multipass-cache-file", "Multipass Cache File",
-          "Multipass cache file",
+          "Multipass cache file. "
+          "If stream caps reinited, multiple files will be created: "
+          "file, file.1, file.2, ... and so on.",
           DEFAULT_MULTIPASS_CACHE_FILE,
           (GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
 
@@ -759,7 +761,9 @@ gst_vp8_enc_init (GstVP8Enc * gst_vp8_enc)
   gst_vp8_enc->cfg.kf_mode = DEFAULT_KF_MODE;
   gst_vp8_enc->cfg.kf_max_dist = DEFAULT_KF_MAX_DIST;
   gst_vp8_enc->cfg.g_pass = DEFAULT_MULTIPASS_MODE;
-  gst_vp8_enc->multipass_cache_file = g_strdup (DEFAULT_MULTIPASS_CACHE_FILE);
+  gst_vp8_enc->multipass_cache_prefix = g_strdup (DEFAULT_MULTIPASS_CACHE_FILE);
+  gst_vp8_enc->multipass_cache_file = NULL;
+  gst_vp8_enc->multipass_cache_idx = 0;
   gst_vp8_enc->cfg.ts_number_layers = DEFAULT_TS_NUMBER_LAYERS;
   gst_vp8_enc->n_ts_target_bitrate = 0;
   gst_vp8_enc->n_ts_rate_decimator = 0;
@@ -801,8 +805,10 @@ gst_vp8_enc_finalize (GObject * object)
   g_return_if_fail (GST_IS_VP8_ENC (object));
   gst_vp8_enc = GST_VP8_ENC (object);
 
+  g_free (gst_vp8_enc->multipass_cache_prefix);
   g_free (gst_vp8_enc->multipass_cache_file);
-  gst_vp8_enc->multipass_cache_file = NULL;
+  gst_vp8_enc->multipass_cache_idx = 0;
+
 
   if (gst_vp8_enc->input_state)
     gst_video_codec_state_unref (gst_vp8_enc->input_state);
@@ -904,9 +910,9 @@ gst_vp8_enc_set_property (GObject * object, guint prop_id,
       global = TRUE;
       break;
     case PROP_MULTIPASS_CACHE_FILE:
-      if (gst_vp8_enc->multipass_cache_file)
+      if (gst_vp8_enc->multipass_cache_prefix)
-        g_free (gst_vp8_enc->multipass_cache_file);
+        g_free (gst_vp8_enc->multipass_cache_prefix);
-      gst_vp8_enc->multipass_cache_file = g_value_dup_string (value);
+      gst_vp8_enc->multipass_cache_prefix = g_value_dup_string (value);
       break;
     case PROP_TS_NUMBER_LAYERS:
       gst_vp8_enc->cfg.ts_number_layers = g_value_get_int (value);
@@ -1264,7 +1270,7 @@ gst_vp8_enc_get_property (GObject * object, guint prop_id, GValue * value,
       g_value_set_enum (value, gst_vp8_enc->cfg.g_pass);
       break;
     case PROP_MULTIPASS_CACHE_FILE:
-      g_value_set_string (value, gst_vp8_enc->multipass_cache_file);
+      g_value_set_string (value, gst_vp8_enc->multipass_cache_prefix);
       break;
     case PROP_TS_NUMBER_LAYERS:
       g_value_set_int (value, gst_vp8_enc->cfg.ts_number_layers);
@@ -1520,6 +1526,7 @@ gst_vp8_enc_set_format (GstVideoEncoder * video_encoder,
     g_mutex_lock (&encoder->encoder_lock);
     vpx_codec_destroy (&encoder->encoder);
     encoder->inited = FALSE;
+    encoder->multipass_cache_idx++;
   } else {
     g_mutex_lock (&encoder->encoder_lock);
   }
@@ -1550,20 +1557,34 @@ gst_vp8_enc_set_format (GstVideoEncoder * video_encoder,
     encoder->cfg.g_timebase.den = 90000;
   }
 
-  if (encoder->cfg.g_pass == VPX_RC_FIRST_PASS) {
+  if (encoder->cfg.g_pass == VPX_RC_FIRST_PASS ||
-    if (encoder->first_pass_cache_content == NULL) {
+      encoder->cfg.g_pass == VPX_RC_LAST_PASS) {
-      encoder->first_pass_cache_content = g_byte_array_sized_new (4096);
+    if (!encoder->multipass_cache_prefix) {
-    }
-  } else if (encoder->cfg.g_pass == VPX_RC_LAST_PASS) {
-    GError *err = NULL;
-
-    if (!encoder->multipass_cache_file) {
       GST_ELEMENT_ERROR (encoder, RESOURCE, OPEN_READ,
           ("No multipass cache file provided"), (NULL));
       g_mutex_unlock (&encoder->encoder_lock);
       return FALSE;
     }
 
+    g_free (encoder->multipass_cache_file);
+
+    if (encoder->multipass_cache_idx > 0)
+      encoder->multipass_cache_file = g_strdup_printf ("%s.%u",
+          encoder->multipass_cache_prefix, encoder->multipass_cache_idx);
+    else
+      encoder->multipass_cache_file =
+          g_strdup (encoder->multipass_cache_prefix);
+  }
+
+  if (encoder->cfg.g_pass == VPX_RC_FIRST_PASS) {
+    if (encoder->first_pass_cache_content != NULL)
+      g_byte_array_free (encoder->first_pass_cache_content, TRUE);
+
+    encoder->first_pass_cache_content = g_byte_array_sized_new (4096);
+
+  } else if (encoder->cfg.g_pass == VPX_RC_LAST_PASS) {
+    GError *err = NULL;
+
     if (encoder->cfg.rc_twopass_stats_in.buf != NULL) {
       g_free (encoder->cfg.rc_twopass_stats_in.buf);
       encoder->cfg.rc_twopass_stats_in.buf = NULL;

ext/vpx/gstvp8enc.h

@@ -73,6 +73,8 @@ struct _GstVP8Enc
   gint n_ts_layer_id;
   /* Global two-pass options */
   gchar *multipass_cache_file;
+  gchar *multipass_cache_prefix;
+  guint multipass_cache_idx;
   GByteArray *first_pass_cache_content;
 
   /* Encode parameter */