[gst-cvs] gst-plugins-good: flvmux: Preallocate index space and fill it after finishing output
Sebastian Dröge
slomo at kemper.freedesktop.org
Mon Mar 15 05:56:52 PDT 2010
Module: gst-plugins-good
Branch: master
Commit: 7deee29d2ca48858ed6fb672246ef4be8c90d951
URL: http://cgit.freedesktop.org/gstreamer/gst-plugins-good/commit/?id=7deee29d2ca48858ed6fb672246ef4be8c90d951
Author: Jan Urbański <wulczer at wulczer.org>
Date: Sun Mar 14 01:38:21 2010 +0100
flvmux: Preallocate index space and fill it after finishing output
Make the index appear at the beginning of the file, which is what most
players are expecting.
Fixes #601236.
---
gst/flv/gstflvmux.c | 179 ++++++++++++++++++++++++++++++--------------------
1 files changed, 107 insertions(+), 72 deletions(-)
diff --git a/gst/flv/gstflvmux.c b/gst/flv/gstflvmux.c
index de2b5ca..2bc568d 100644
--- a/gst/flv/gstflvmux.c
+++ b/gst/flv/gstflvmux.c
@@ -50,6 +50,7 @@ enum
};
#define DEFAULT_IS_LIVE FALSE
+#define MAX_INDEX_ENTRIES 128
static GstStaticPadTemplate src_templ = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
@@ -566,6 +567,36 @@ gst_flv_mux_push (GstFlvMux * mux, GstBuffer * buffer)
return gst_pad_push (mux->srcpad, buffer);
}
+static GstBuffer *
+gst_flv_mux_preallocate_index (GstFlvMux * mux)
+{
+ GstBuffer *tmp;
+ guint8 *data;
+ gint preallocate_size;
+
+ /* preallocate index of size:
+ * - 'keyframes' ECMA array key: 2 + 9 = 11 bytes
+ * - nested ECMA array header, length and end marker: 8 bytes
+ * - 'times' and 'filepositions' keys: 22 bytes
+ * - two strict arrays headers and lengths: 10 bytes
+ * - each index entry: 18 bytes
+ */
+ preallocate_size = 11 + 8 + 22 + 10 + MAX_INDEX_ENTRIES * 18;
+ GST_DEBUG_OBJECT (mux, "preallocating %d bytes for the index",
+ preallocate_size);
+
+ tmp = gst_buffer_new_and_alloc (preallocate_size);
+ data = GST_BUFFER_DATA (tmp);
+
+ /* prefill the space with a gstfiller: <spaces> script tag variable */
+ GST_WRITE_UINT16_BE (data, 9); /* 9 characters */
+ memcpy (data + 2, "gstfiller", 9);
+ GST_WRITE_UINT8 (data + 11, 2); /* a string value */
+ GST_WRITE_UINT16_BE (data + 12, preallocate_size - 14);
+ memset (data + 14, ' ', preallocate_size - 14); /* the rest is spaces */
+ return tmp;
+}
+
static GstFlowReturn
gst_flv_mux_write_metadata (GstFlvMux * mux)
{
@@ -612,6 +643,13 @@ gst_flv_mux_write_metadata (GstFlvMux * mux)
GST_WRITE_UINT32_BE (data + 1, n_tags);
script_tag = gst_buffer_join (script_tag, tmp);
+ if (!mux->is_live) {
+ tmp = gst_flv_mux_preallocate_index (mux);
+ script_tag = gst_buffer_join (script_tag, tmp);
+ } else {
+ GST_DEBUG_OBJECT (mux, "not preallocating index, stream is live");
+ }
+
for (i = 0; tags && i < n_tags; i++) {
const gchar *tag_name =
gst_structure_nth_field_name ((const GstStructure *) tags, i);
@@ -1010,113 +1048,110 @@ static GstFlowReturn
gst_flv_mux_write_index (GstFlvMux * mux)
{
GstFlowReturn ret = GST_FLOW_OK;
- GstBuffer *script_tag, *tmp;
+ GstBuffer *index;
+ GstEvent *event;
guint8 *data;
GList *l;
- guint32 index_len;
+ guint32 index_len, allocate_size;
guint32 i, index_skip;
if (!mux->index)
return GST_FLOW_OK;
- script_tag = gst_buffer_new_and_alloc (11);
- data = GST_BUFFER_DATA (script_tag);
-
- data[0] = 18;
-
- /* Data size, unknown for now */
- data[1] = 0;
- data[2] = 0;
- data[3] = 0;
-
- /* Timestamp */
- data[4] = data[5] = data[6] = data[7] = 0;
-
- /* Stream ID */
- data[8] = data[9] = data[10] = 0;
-
- tmp = gst_buffer_new_and_alloc (13);
- data = GST_BUFFER_DATA (tmp);
- data[0] = 2; /* string */
- data[1] = 0;
- data[2] = 0x0a; /* length 10 */
- memcpy (&data[3], "onMetaData", 10);
-
- script_tag = gst_buffer_join (script_tag, tmp);
+ if (mux->is_live)
+ return GST_FLOW_OK;
- tmp = gst_buffer_new_and_alloc (5);
- data = GST_BUFFER_DATA (tmp);
- data[0] = 8; /* ECMA array */
- GST_WRITE_UINT32_BE (data + 1, 2);
- script_tag = gst_buffer_join (script_tag, tmp);
+ /* seek back to the preallocated index space */
+ event = gst_event_new_new_segment (FALSE, 1.0, GST_FORMAT_BYTES,
+ 42, GST_CLOCK_TIME_NONE, 42);
+ if (!gst_pad_push_event (mux->srcpad, event)) {
+ GST_WARNING_OBJECT (mux, "Seek to rewrite index failed");
+ return GST_FLOW_OK;
+ }
mux->index = g_list_reverse (mux->index);
index_len = g_list_length (mux->index);
- /* We write at most 128 elements */
- index_skip = (index_len > 128) ? 1 + index_len / 128 : 1;
- index_len =
- (index_len <=
- 128) ? index_len : (index_len + index_skip - 1) / index_skip;
-
- tmp = gst_buffer_new_and_alloc (2 + 5 + 1 + 4 + index_len * (1 + 8));
- data = GST_BUFFER_DATA (tmp);
- data[0] = 0; /* 5 bytes name */
- data[1] = 5;
- memcpy (&data[2], "times", 5);
- data[7] = 10; /* array */
- GST_WRITE_UINT32_BE (&data[8], index_len);
- data += 12;
+ /* We write at most MAX_INDEX_ENTRIES elements */
+ if (index_len > MAX_INDEX_ENTRIES) {
+ index_skip = 1 + index_len / MAX_INDEX_ENTRIES;
+ index_len = (index_len + index_skip - 1) / index_skip;
+ } else {
+ index_skip = 1;
+ }
+ GST_DEBUG_OBJECT (mux, "Index length is %d", index_len);
+ /* see size calculation in gst_flv_mux_preallocate_index */
+ allocate_size = 11 + 8 + 22 + 10 + index_len * 18;
+ GST_DEBUG_OBJECT (mux, "Allocating %d bytes for index", allocate_size);
+ index = gst_buffer_new_and_alloc (allocate_size);
+ data = GST_BUFFER_DATA (index);
+
+ GST_WRITE_UINT16_BE (data, 9); /* the 'keyframes' key */
+ memcpy (data + 2, "keyframes", 9);
+ GST_WRITE_UINT8 (data + 11, 8); /* nested ECMA array */
+ GST_WRITE_UINT32_BE (data + 12, 2); /* two elements */
+ GST_WRITE_UINT16_BE (data + 16, 5); /* first string key: 'times' */
+ memcpy (data + 18, "times", 5);
+ GST_WRITE_UINT8 (data + 23, 10); /* strict array */
+ GST_WRITE_UINT32_BE (data + 24, index_len);
+ data += 28;
+
+ /* the keyframes' times */
for (i = 0, l = mux->index; l; l = l->next, i++) {
GstFlvMuxIndexEntry *entry = l->data;
if (i % index_skip != 0)
continue;
-
- data[0] = 0;
- GST_WRITE_DOUBLE_BE (&data[1], entry->time);
+ GST_WRITE_UINT8 (data, 0); /* numeric (aka double) */
+ GST_WRITE_DOUBLE_BE (data + 1, entry->time);
data += 9;
}
- script_tag = gst_buffer_join (script_tag, tmp);
- tmp = gst_buffer_new_and_alloc (2 + 13 + 1 + 4 + index_len * (1 + 8));
- data = GST_BUFFER_DATA (tmp);
- data[0] = 0; /* 13 bytes name */
- data[1] = 13;
- memcpy (&data[2], "filepositions", 13);
- data[15] = 10; /* array */
- GST_WRITE_UINT32_BE (&data[16], index_len);
+ GST_WRITE_UINT16_BE (data, 13); /* second string key: 'filepositions' */
+ memcpy (data + 2, "filepositions", 13);
+ GST_WRITE_UINT8 (data + 15, 10); /* strict array */
+ GST_WRITE_UINT32_BE (data + 16, index_len);
data += 20;
+ /* the keyframes' file positions */
for (i = 0, l = mux->index; l; l = l->next, i++) {
GstFlvMuxIndexEntry *entry = l->data;
if (i % index_skip != 0)
continue;
- data[0] = 0;
- GST_WRITE_DOUBLE_BE (&data[1], entry->position);
+ GST_WRITE_UINT8 (data, 0);
+ GST_WRITE_DOUBLE_BE (data + 1, entry->position);
data += 9;
}
- script_tag = gst_buffer_join (script_tag, tmp);
- tmp = gst_buffer_new_and_alloc (3);
- data = GST_BUFFER_DATA (tmp);
GST_WRITE_UINT24_BE (data, 9); /* finish the ECMA array */
- script_tag = gst_buffer_join (script_tag, tmp);
- tmp = gst_buffer_new_and_alloc (4);
- data = GST_BUFFER_DATA (tmp);
- GST_WRITE_UINT32_BE (data, GST_BUFFER_SIZE (script_tag));
- script_tag = gst_buffer_join (script_tag, tmp);
+ /* If there is space left in the prefilled area, reinsert the filler.
+ There is at least 18 bytes free, so it will always fit. */
+ if (index_len < MAX_INDEX_ENTRIES) {
+ GstBuffer *tmp;
+ guint8 *data;
+ guint32 remaining_filler_size;
- data = GST_BUFFER_DATA (script_tag);
- data[1] = ((GST_BUFFER_SIZE (script_tag) - 11 - 4) >> 16) & 0xff;
- data[2] = ((GST_BUFFER_SIZE (script_tag) - 11 - 4) >> 8) & 0xff;
- data[3] = ((GST_BUFFER_SIZE (script_tag) - 11 - 4) >> 0) & 0xff;
+ tmp = gst_buffer_new_and_alloc (14);
+ data = GST_BUFFER_DATA (tmp);
+ GST_WRITE_UINT16_BE (data, 9);
+ memcpy (data + 2, "gstfiller", 9);
+ GST_WRITE_UINT8 (data + 11, 2); /* string */
+
+ /* There is 18 bytes per remaining index entry minus what is used for
+ * the'gstfiller' key. The rest is already filled with spaces, so just need
+ * to update length. */
+ remaining_filler_size = (MAX_INDEX_ENTRIES - index_len) * 18 - 14;
+ GST_DEBUG_OBJECT (mux, "Remaining filler size is %d bytes",
+ remaining_filler_size);
+ GST_WRITE_UINT16_BE (data + 12, remaining_filler_size);
+ index = gst_buffer_join (index, tmp);
+ }
- gst_buffer_set_caps (script_tag, GST_PAD_CAPS (mux->srcpad));
- ret = gst_flv_mux_push (mux, script_tag);
+ gst_buffer_set_caps (index, GST_PAD_CAPS (mux->srcpad));
+ ret = gst_flv_mux_push (mux, index);
return ret;
}
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