gst/playback/gstdecodebin.c: Special-case the text/plain media type: we only want to recognise it as a 'raw' decoded ...

Original commit message from CVS:
* gst/playback/gstdecodebin.c: (type_found):
Special-case the text/plain media type: we only want to recognise it
as a 'raw' decoded media type if it comes from a demuxer or subtitle
parser, but not if the entire stream is of text/plain type. If the
entire stream is text/plain, we should just error out.
This fixes playback of audio files with lyrics in totem. Totem can't
distinguish between text files and subtitle files and passes any
.txt file with the same basename as the main file to playbin as
suburi, and playbin will then throw a 'subtitle found, but no video
stream' error, which isn't entirely helpful. See #380342.
Also, with this change we'll show a slightly more correct error
message in case totem passes a playlist file to us (although a
custom error message wording instead of the default text would
probably not be a bad idea either).
Same problem also needs to be fixed for playbin+decodebin2.
* tests/check/Makefile.am:
* tests/check/elements/decodebin.c: (src_handoff_cb),
(decodebin_new_decoded_pad_cb), (GST_START_TEST),
(decodebin_suite):
Add simple unit test for decodebin for the above.

ChangeLog

@@ -1,3 +1,30 @@
+2006-12-16  Tim-Philipp Müller  <tim at centricular dot net>
+
+	* gst/playback/gstdecodebin.c: (type_found):
+	  Special-case the text/plain media type: we only want to recognise it
+	  as a 'raw' decoded media type if it comes from a demuxer or subtitle
+	  parser, but not if the entire stream is of text/plain type. If the
+	  entire stream is text/plain, we should just error out.
+
+	  This fixes playback of audio files with lyrics in totem. Totem can't
+	  distinguish between text files and subtitle files and passes any
+	  .txt file with the same basename as the main file to playbin as
+	  suburi, and playbin will then throw a 'subtitle found, but no video
+	  stream' error, which isn't entirely helpful. See #380342.
+
+	  Also, with this change we'll show a slightly more correct error
+	  message in case totem passes a playlist file to us (although a
+	  custom error message wording instead of the default text would
+	  probably not be a bad idea either).
+
+	  Same problem also needs to be fixed for playbin+decodebin2.
+
+	* tests/check/Makefile.am:
+	* tests/check/elements/decodebin.c: (src_handoff_cb),
+	(decodebin_new_decoded_pad_cb), (GST_START_TEST),
+	(decodebin_suite):
+	  Add simple unit test for decodebin for the above.
+
 2006-12-16  Tim-Philipp Müller  <tim at centricular dot net>
 
 	* gst/playback/gstdecodebin.c: (gst_decode_bin_change_state):

gst/playback/gstdecodebin.c

@@ -1541,6 +1541,18 @@ type_found (GstElement * typefind, guint probability, GstCaps * caps,
 
   GST_DEBUG_OBJECT (decode_bin, "typefind found caps %" GST_PTR_FORMAT, caps);
 
+  /* special-case text/plain: we only want to accept it as a raw type if it
+   * comes from a subtitel parser element or a demuxer, but not if it is the
+   * type of the entire stream, in which case we just want to error out */
+  if (typefind == decode_bin->typefind &&
+      gst_structure_has_name (gst_caps_get_structure (caps, 0), "text/plain")) {
+    gst_element_no_more_pads (GST_ELEMENT (decode_bin));
+    /* we can't handle this type of stream */
+    GST_ELEMENT_ERROR (decode_bin, STREAM, WRONG_TYPE, (NULL),
+        ("decodebin cannot decode plain text files"));
+    goto shutting_down;
+  }
+
   /* autoplug the new pad with the caps that the signal gave us. */
   pad = gst_element_get_pad (typefind, "src");
   close_pad_link (typefind, pad, caps, decode_bin, FALSE);

tests/check/Makefile.am

@@ -62,6 +62,7 @@ check_PROGRAMS = \
 	elements/audiorate \
 	elements/audioresample \
 	elements/audiotestsrc \
+	elements/decodebin \
 	elements/ffmpegcolorspace \
 	elements/gdpdepay \
 	elements/gdppay \
@@ -147,6 +148,9 @@ elements_gdppay_LDADD = $(GST_GDP_LIBS) $(LDADD)
 elements_playbin_LDADD = $(GST_BASE_LIBS) $(LDADD)
 elements_playbin_CFLAGS = $(GST_BASE_CFLAGS) $(AM_CFLAGS)
 
+elements_decodebin_LDADD = $(GST_BASE_LIBS) $(LDADD)
+elements_decodebin_CFLAGS = $(GST_BASE_CFLAGS) $(AM_CFLAGS)
+
 elements_subparse_LDADD =  $(LDADD)
 elements_subparse_CFLAGS = $(CFLAGS) $(AM_CFLAGS)
 

tests/check/elements/decodebin.c

@@ -0,0 +1,118 @@
+/* GStreamer unit tests for decodebin
+ *
+ * Copyright (C) 2006 Tim-Philipp Müller <tim centricular net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <gst/check/gstcheck.h>
+#include <unistd.h>
+
+const gchar dummytext[] = "Quick Brown Fox Jumps over a Lazy Frog Quick Brown "
+    "Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a Lazy Frog Quick "
+    "Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a Lazy Frog "
+    "Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a Lazy "
+    "Frog Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a "
+    "Lazy Frog Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps "
+    "over a Lazy Frog Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox "
+    "jumps over a Lazy Frog Quick Brown Fox Jumps over a Lazy Frog Quick Brown "
+    "Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a Lazy Frog Quick "
+    "Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a Lazy Frog "
+    "Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a Lazy "
+    "Frog Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps over a "
+    "Lazy Frog Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox Jumps "
+    "over a Lazy Frog Quick Brown Fox Jumps over a Lazy Frog Quick Brown Fox ";
+
+static void
+src_handoff_cb (GstElement * src, GstBuffer * buf, GstPad * pad, gpointer data)
+{
+  GST_BUFFER_DATA (buf) = (guint8 *) dummytext;
+  GST_BUFFER_SIZE (buf) = sizeof (dummytext);
+  GST_BUFFER_OFFSET (buf) = 0;
+  GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_READONLY);
+}
+
+static void
+decodebin_new_decoded_pad_cb (GstElement * decodebin, GstPad * pad,
+    gboolean last, gboolean * p_flag)
+{
+  /* we should not be reached */
+  fail_unless (decodebin == NULL, "new-decoded-pad should not be emitted");
+}
+
+/* make sure that decodebin errors out instead of creating a new decoded pad
+ * if the entire stream is a plain text file */
+GST_START_TEST (test_text_plain_streams)
+{
+  GstElement *pipe, *src, *decodebin;
+  GstMessage *msg;
+
+  pipe = gst_pipeline_new (NULL);
+  fail_unless (pipe != NULL, "failed to create pipeline");
+
+  src = gst_element_factory_make ("fakesrc", "src");
+  fail_unless (src != NULL, "Failed to create fakesrc element");
+
+  g_object_set (src, "signal-handoffs", TRUE, NULL);
+  g_object_set (src, "num-buffers", 1, NULL);
+  g_signal_connect (src, "handoff", G_CALLBACK (src_handoff_cb), NULL);
+
+  decodebin = gst_element_factory_make ("decodebin", "decodebin");
+  fail_unless (decodebin != NULL, "Failed to create decodebin element");
+
+  g_signal_connect (decodebin, "new-decoded-pad",
+      G_CALLBACK (decodebin_new_decoded_pad_cb), NULL);
+
+  fail_unless (gst_bin_add (GST_BIN (pipe), src));
+  fail_unless (gst_bin_add (GST_BIN (pipe), decodebin));
+  fail_unless (gst_element_link (src, decodebin), "can't link src<->decodebin");
+
+  fail_unless_equals_int (gst_element_set_state (pipe, GST_STATE_READY),
+      GST_STATE_CHANGE_SUCCESS);
+  /* it's push-based, so should be async */
+  fail_unless_equals_int (gst_element_set_state (pipe, GST_STATE_PAUSED),
+      GST_STATE_CHANGE_ASYNC);
+
+  /* it should error out at some point */
+  msg = gst_bus_poll (GST_ELEMENT_BUS (pipe), GST_MESSAGE_ERROR, -1);
+  fail_unless (msg != NULL);
+  fail_unless (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_ERROR);
+  gst_message_unref (msg);
+
+  gst_element_set_state (pipe, GST_STATE_NULL);
+  gst_object_unref (pipe);
+}
+
+GST_END_TEST;
+
+static Suite *
+decodebin_suite (void)
+{
+  Suite *s = suite_create ("decodebin");
+  TCase *tc_chain = tcase_create ("general");
+
+  suite_add_tcase (s, tc_chain);
+
+  tcase_add_test (tc_chain, test_text_plain_streams);
+
+  return s;
+}
+
+GST_CHECK_MAIN (decodebin);