gstreamer/gst/audioparsers/gstflacparse.c
Sebastian Dröge 812075dc5d flacparse: Simplify frame header parsing by using lookup tables
Based on a patch by Felipe Contreras.

See bug #631200.
2010-10-07 23:38:26 +02:00

1284 lines
40 KiB
C

/* GStreamer
*
* Copyright (C) 2008 Sebastian Dröge <sebastian.droege@collabora.co.uk>.
* Copyright (C) 2009 Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
* Copyright (C) 2009 Nokia Corporation. All rights reserved.
* Contact: Stefan Kost <stefan.kost@nokia.com>
*
* 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.
*/
/**
* SECTION:element-flacparse
* @see_also: flacdec, oggdemux, vorbisparse
*
* The flacparse element will parse the header packets of the FLAC
* stream and put them as the streamheader in the caps. This is used in the
* multifdsink case where you want to stream live FLAC streams to multiple
* clients, each client has to receive the streamheaders first before they can
* consume the FLAC packets.
*
* This element also makes sure that the buffers that it pushes out are properly
* timestamped and that their offset and offset_end are set. The buffers that
* flacparse outputs have all of the metadata that oggmux expects to receive,
* which allows you to (for example) remux an ogg/flac or convert a native FLAC
* format file to an ogg bitstream.
*
* <refsect2>
* <title>Example pipelines</title>
* |[
* gst-launch -v filesrc location=sine.flac ! flacparse ! identity \
* ! oggmux ! filesink location=sine-remuxed.ogg
* ]| This pipeline converts a native FLAC format file to an ogg bitstream.
* It also illustrates that the streamheader is set in the caps, and that each
* buffer has the timestamp, duration, offset, and offset_end set.
* </refsect2>
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstflacparse.h"
#include <string.h>
#include <gst/tag/tag.h>
#include <gst/audio/audio.h>
#include <gst/base/gstbitreader.h>
#include <gst/base/gstbytereader.h>
GST_DEBUG_CATEGORY_STATIC (flacparse_debug);
#define GST_CAT_DEFAULT flacparse_debug
/* CRC-8, poly = x^8 + x^2 + x^1 + x^0, init = 0 */
static const guint8 crc8_table[256] = {
0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15,
0x38, 0x3F, 0x36, 0x31, 0x24, 0x23, 0x2A, 0x2D,
0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D,
0xE0, 0xE7, 0xEE, 0xE9, 0xFC, 0xFB, 0xF2, 0xF5,
0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85,
0xA8, 0xAF, 0xA6, 0xA1, 0xB4, 0xB3, 0xBA, 0xBD,
0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA,
0xB7, 0xB0, 0xB9, 0xBE, 0xAB, 0xAC, 0xA5, 0xA2,
0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32,
0x1F, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0D, 0x0A,
0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A,
0x89, 0x8E, 0x87, 0x80, 0x95, 0x92, 0x9B, 0x9C,
0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC,
0xC1, 0xC6, 0xCF, 0xC8, 0xDD, 0xDA, 0xD3, 0xD4,
0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44,
0x19, 0x1E, 0x17, 0x10, 0x05, 0x02, 0x0B, 0x0C,
0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B,
0x76, 0x71, 0x78, 0x7F, 0x6A, 0x6D, 0x64, 0x63,
0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13,
0xAE, 0xA9, 0xA0, 0xA7, 0xB2, 0xB5, 0xBC, 0xBB,
0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB,
0xE6, 0xE1, 0xE8, 0xEF, 0xFA, 0xFD, 0xF4, 0xF3
};
static guint8
gst_flac_calculate_crc8 (const guint8 * data, guint length)
{
guint8 crc = 0;
while (length--) {
crc = crc8_table[crc ^ *data];
++data;
}
return crc;
}
/* CRC-16, poly = x^16 + x^15 + x^2 + x^0, init = 0 */
static const guint16 crc16_table[256] = {
0x0000, 0x8005, 0x800f, 0x000a, 0x801b, 0x001e, 0x0014, 0x8011,
0x8033, 0x0036, 0x003c, 0x8039, 0x0028, 0x802d, 0x8027, 0x0022,
0x8063, 0x0066, 0x006c, 0x8069, 0x0078, 0x807d, 0x8077, 0x0072,
0x0050, 0x8055, 0x805f, 0x005a, 0x804b, 0x004e, 0x0044, 0x8041,
0x80c3, 0x00c6, 0x00cc, 0x80c9, 0x00d8, 0x80dd, 0x80d7, 0x00d2,
0x00f0, 0x80f5, 0x80ff, 0x00fa, 0x80eb, 0x00ee, 0x00e4, 0x80e1,
0x00a0, 0x80a5, 0x80af, 0x00aa, 0x80bb, 0x00be, 0x00b4, 0x80b1,
0x8093, 0x0096, 0x009c, 0x8099, 0x0088, 0x808d, 0x8087, 0x0082,
0x8183, 0x0186, 0x018c, 0x8189, 0x0198, 0x819d, 0x8197, 0x0192,
0x01b0, 0x81b5, 0x81bf, 0x01ba, 0x81ab, 0x01ae, 0x01a4, 0x81a1,
0x01e0, 0x81e5, 0x81ef, 0x01ea, 0x81fb, 0x01fe, 0x01f4, 0x81f1,
0x81d3, 0x01d6, 0x01dc, 0x81d9, 0x01c8, 0x81cd, 0x81c7, 0x01c2,
0x0140, 0x8145, 0x814f, 0x014a, 0x815b, 0x015e, 0x0154, 0x8151,
0x8173, 0x0176, 0x017c, 0x8179, 0x0168, 0x816d, 0x8167, 0x0162,
0x8123, 0x0126, 0x012c, 0x8129, 0x0138, 0x813d, 0x8137, 0x0132,
0x0110, 0x8115, 0x811f, 0x011a, 0x810b, 0x010e, 0x0104, 0x8101,
0x8303, 0x0306, 0x030c, 0x8309, 0x0318, 0x831d, 0x8317, 0x0312,
0x0330, 0x8335, 0x833f, 0x033a, 0x832b, 0x032e, 0x0324, 0x8321,
0x0360, 0x8365, 0x836f, 0x036a, 0x837b, 0x037e, 0x0374, 0x8371,
0x8353, 0x0356, 0x035c, 0x8359, 0x0348, 0x834d, 0x8347, 0x0342,
0x03c0, 0x83c5, 0x83cf, 0x03ca, 0x83db, 0x03de, 0x03d4, 0x83d1,
0x83f3, 0x03f6, 0x03fc, 0x83f9, 0x03e8, 0x83ed, 0x83e7, 0x03e2,
0x83a3, 0x03a6, 0x03ac, 0x83a9, 0x03b8, 0x83bd, 0x83b7, 0x03b2,
0x0390, 0x8395, 0x839f, 0x039a, 0x838b, 0x038e, 0x0384, 0x8381,
0x0280, 0x8285, 0x828f, 0x028a, 0x829b, 0x029e, 0x0294, 0x8291,
0x82b3, 0x02b6, 0x02bc, 0x82b9, 0x02a8, 0x82ad, 0x82a7, 0x02a2,
0x82e3, 0x02e6, 0x02ec, 0x82e9, 0x02f8, 0x82fd, 0x82f7, 0x02f2,
0x02d0, 0x82d5, 0x82df, 0x02da, 0x82cb, 0x02ce, 0x02c4, 0x82c1,
0x8243, 0x0246, 0x024c, 0x8249, 0x0258, 0x825d, 0x8257, 0x0252,
0x0270, 0x8275, 0x827f, 0x027a, 0x826b, 0x026e, 0x0264, 0x8261,
0x0220, 0x8225, 0x822f, 0x022a, 0x823b, 0x023e, 0x0234, 0x8231,
0x8213, 0x0216, 0x021c, 0x8219, 0x0208, 0x820d, 0x8207, 0x0202
};
static guint16
gst_flac_calculate_crc16 (const guint8 * data, guint length)
{
guint16 crc = 0;
while (length--) {
crc = ((crc << 8) ^ crc16_table[(crc >> 8) ^ *data]) & 0xffff;
data++;
}
return crc;
}
enum
{
PROP_0,
PROP_CHECK_FRAME_CHECKSUMS
};
#define DEFAULT_CHECK_FRAME_CHECKSUMS FALSE
static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-flac, framed = (boolean) true, "
"channels = (int) [ 1, 8 ], " "rate = (int) [ 1, 655350 ]")
);
static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-flac, framed = (boolean) false")
);
static void gst_flac_parse_finalize (GObject * object);
static void gst_flac_parse_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_flac_parse_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_flac_parse_start (GstBaseParse * parse);
static gboolean gst_flac_parse_stop (GstBaseParse * parse);
static gboolean gst_flac_parse_check_valid_frame (GstBaseParse * parse,
GstBuffer * buffer, guint * framesize, gint * skipsize);
static GstFlowReturn gst_flac_parse_parse_frame (GstBaseParse * parse,
GstBuffer * buffer);
static gint gst_flac_parse_get_frame_overhead (GstBaseParse * parse,
GstBuffer * buffer);
static GstFlowReturn gst_flac_parse_pre_push_buffer (GstBaseParse * parse,
GstBuffer * buf);
GST_BOILERPLATE (GstFlacParse, gst_flac_parse, GstBaseParse,
GST_TYPE_BASE_PARSE);
static void
gst_flac_parse_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_factory));
gst_element_class_set_details_simple (element_class, "FLAC audio parser",
"Codec/Parser/Audio",
"Parses audio with the FLAC lossless audio codec",
"Sebastian Dröge <sebastian.droege@collabora.co.uk>");
GST_DEBUG_CATEGORY_INIT (flacparse_debug, "flacparse", 0,
"Flac parser element");
}
static void
gst_flac_parse_class_init (GstFlacParseClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstBaseParseClass *baseparse_class = GST_BASE_PARSE_CLASS (klass);
gobject_class->finalize = gst_flac_parse_finalize;
gobject_class->set_property = gst_flac_parse_set_property;
gobject_class->get_property = gst_flac_parse_get_property;
g_object_class_install_property (gobject_class, PROP_CHECK_FRAME_CHECKSUMS,
g_param_spec_boolean ("check-frame-checksums", "Check Frame Checksums",
"Check the overall checksums of every frame",
DEFAULT_CHECK_FRAME_CHECKSUMS,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
baseparse_class->start = GST_DEBUG_FUNCPTR (gst_flac_parse_start);
baseparse_class->stop = GST_DEBUG_FUNCPTR (gst_flac_parse_stop);
baseparse_class->check_valid_frame =
GST_DEBUG_FUNCPTR (gst_flac_parse_check_valid_frame);
baseparse_class->parse_frame = GST_DEBUG_FUNCPTR (gst_flac_parse_parse_frame);
baseparse_class->get_frame_overhead =
GST_DEBUG_FUNCPTR (gst_flac_parse_get_frame_overhead);
baseparse_class->pre_push_buffer =
GST_DEBUG_FUNCPTR (gst_flac_parse_pre_push_buffer);
}
static void
gst_flac_parse_init (GstFlacParse * flacparse, GstFlacParseClass * klass)
{
flacparse->check_frame_checksums = DEFAULT_CHECK_FRAME_CHECKSUMS;
}
static void
gst_flac_parse_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (object);
switch (prop_id) {
case PROP_CHECK_FRAME_CHECKSUMS:
flacparse->check_frame_checksums = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_flac_parse_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (object);
switch (prop_id) {
case PROP_CHECK_FRAME_CHECKSUMS:
g_value_set_boolean (value, flacparse->check_frame_checksums);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_flac_parse_finalize (GObject * object)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (object);
if (flacparse->tags) {
gst_tag_list_free (flacparse->tags);
flacparse->tags = NULL;
}
g_list_foreach (flacparse->headers, (GFunc) gst_mini_object_unref, NULL);
g_list_free (flacparse->headers);
flacparse->headers = NULL;
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static gboolean
gst_flac_parse_start (GstBaseParse * parse)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (parse);
flacparse->state = GST_FLAC_PARSE_STATE_INIT;
flacparse->min_blocksize = 0;
flacparse->max_blocksize = 0;
flacparse->min_framesize = 0;
flacparse->max_framesize = 0;
flacparse->upstream_length = -1;
flacparse->samplerate = 0;
flacparse->channels = 0;
flacparse->bps = 0;
flacparse->total_samples = 0;
flacparse->offset = GST_CLOCK_TIME_NONE;
flacparse->blocking_strategy = 0;
flacparse->block_size = 0;
flacparse->sample_number = 0;
/* "fLaC" marker */
gst_base_parse_set_min_frame_size (GST_BASE_PARSE (flacparse), 4);
return TRUE;
}
static gboolean
gst_flac_parse_stop (GstBaseParse * parse)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (parse);
if (flacparse->tags) {
gst_tag_list_free (flacparse->tags);
flacparse->tags = NULL;
}
g_list_foreach (flacparse->headers, (GFunc) gst_mini_object_unref, NULL);
g_list_free (flacparse->headers);
flacparse->headers = NULL;
return TRUE;
}
static const guint8 sample_size_table[] = { 0, 8, 12, 0, 16, 20, 24, 0 };
static const guint16 blocksize_table[16] = {
0, 192, 576 << 0, 576 << 1, 576 << 2, 576 << 3, 0, 0,
256 << 0, 256 << 1, 256 << 2, 256 << 3, 256 << 4, 256 << 5, 256 << 6,
256 << 7,
};
static const guint32 sample_rate_table[16] = {
0,
88200, 176400, 192000,
8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
0, 0, 0, 0,
};
typedef enum
{
FRAME_HEADER_VALID,
FRAME_HEADER_INVALID,
FRAME_HEADER_MORE_DATA
} FrameHeaderCheckReturn;
static FrameHeaderCheckReturn
gst_flac_parse_frame_header_is_valid (GstFlacParse * flacparse,
const guint8 * data, guint size, gboolean set, guint16 * block_size_ret)
{
GstBitReader reader = GST_BIT_READER_INIT (data, size);
guint8 blocking_strategy;
guint16 block_size;
guint32 samplerate = 0;
guint64 sample_number;
guint8 channels, bps;
guint8 tmp = 0;
guint8 actual_crc, expected_crc = 0;
/* Skip 14 bit sync code */
gst_bit_reader_skip_unchecked (&reader, 14);
/* Must be 0 */
if (gst_bit_reader_get_bits_uint8_unchecked (&reader, 1) != 0)
goto error;
/* 0 == fixed block size, 1 == variable block size */
blocking_strategy = gst_bit_reader_get_bits_uint8_unchecked (&reader, 1);
/* block size index, calculation of the real blocksize below */
block_size = gst_bit_reader_get_bits_uint16_unchecked (&reader, 4);
if (block_size == 0)
goto error;
/* sample rate index, calculation of the real samplerate below */
samplerate = gst_bit_reader_get_bits_uint16_unchecked (&reader, 4);
if (samplerate == 0x0f)
goto error;
/* channel assignment */
channels = gst_bit_reader_get_bits_uint8_unchecked (&reader, 4);
if (channels < 8) {
channels++;
} else if (channels <= 10) {
channels = 2;
} else if (channels > 10) {
goto error;
}
if (flacparse->channels && flacparse->channels != channels)
goto error;
/* bits per sample */
bps = gst_bit_reader_get_bits_uint8_unchecked (&reader, 3);
if (bps == 0x03 || bps == 0x07) {
goto error;
} else if (bps == 0 && flacparse->bps == 0) {
goto need_streaminfo;
}
bps = sample_size_table[bps];
if (flacparse->bps && bps != flacparse->bps)
goto error;
/* reserved, must be 0 */
if (gst_bit_reader_get_bits_uint8_unchecked (&reader, 1) != 0)
goto error;
/* read "utf8" encoded sample/frame number */
{
gint len = 0;
len = gst_bit_reader_get_bits_uint8_unchecked (&reader, 8);
/* This is slightly faster than a loop */
if (!(len & 0x80)) {
sample_number = len;
len = 0;
} else if ((len & 0xc0) && !(len & 0x20)) {
sample_number = len & 0x1f;
len = 1;
} else if ((len & 0xe0) && !(len & 0x10)) {
sample_number = len & 0x0f;
len = 2;
} else if ((len & 0xf0) && !(len & 0x08)) {
sample_number = len & 0x07;
len = 3;
} else if ((len & 0xf8) && !(len & 0x04)) {
sample_number = len & 0x03;
len = 4;
} else if ((len & 0xfc) && !(len & 0x02)) {
sample_number = len & 0x01;
len = 5;
} else if ((len & 0xfe) && !(len & 0x01)) {
sample_number = len & 0x0;
len = 6;
} else {
goto error;
}
if ((blocking_strategy == 0 && len > 5) ||
(blocking_strategy == 1 && len > 6))
goto error;
while (len > 0) {
if (!gst_bit_reader_get_bits_uint8 (&reader, &tmp, 8))
goto need_more_data;
if ((tmp & 0xc0) != 0x80)
goto error;
sample_number <<= 6;
sample_number |= (tmp & 0x3f);
len--;
}
}
/* calculate real blocksize from the blocksize index */
if (block_size == 0) {
goto error;
} else if (block_size == 6) {
if (!gst_bit_reader_get_bits_uint16 (&reader, &block_size, 8))
goto need_more_data;
block_size++;
} else if (block_size == 7) {
if (!gst_bit_reader_get_bits_uint16 (&reader, &block_size, 16))
goto need_more_data;
block_size++;
} else {
block_size = blocksize_table[block_size];
}
/* calculate the real samplerate from the samplerate index */
if (samplerate == 0 && flacparse->samplerate == 0) {
goto need_streaminfo;
} else if (samplerate < 12) {
samplerate = sample_rate_table[samplerate];
} else if (samplerate == 12) {
if (!gst_bit_reader_get_bits_uint32 (&reader, &samplerate, 8))
goto need_more_data;
samplerate *= 1000;
} else if (samplerate == 13) {
if (!gst_bit_reader_get_bits_uint32 (&reader, &samplerate, 16))
goto need_more_data;
} else if (samplerate == 14) {
if (!gst_bit_reader_get_bits_uint32 (&reader, &samplerate, 16))
goto need_more_data;
samplerate *= 10;
}
if (flacparse->samplerate && flacparse->samplerate != samplerate)
goto error;
/* check crc-8 for the header */
if (!gst_bit_reader_get_bits_uint8 (&reader, &expected_crc, 8))
goto need_more_data;
actual_crc =
gst_flac_calculate_crc8 (data,
(gst_bit_reader_get_pos (&reader) / 8) - 1);
if (actual_crc != expected_crc)
goto error;
if (set) {
flacparse->block_size = block_size;
if (!flacparse->samplerate)
flacparse->samplerate = samplerate;
if (!flacparse->bps)
flacparse->bps = bps;
if (!flacparse->blocking_strategy)
flacparse->blocking_strategy = blocking_strategy;
if (!flacparse->channels)
flacparse->channels = channels;
if (!flacparse->sample_number)
flacparse->sample_number = sample_number;
GST_DEBUG_OBJECT (flacparse,
"Parsed frame at offset %" G_GUINT64_FORMAT ":\n" "Block size: %u\n"
"Sample/Frame number: %" G_GUINT64_FORMAT, flacparse->offset,
flacparse->block_size, flacparse->sample_number);
}
if (block_size_ret)
*block_size_ret = block_size;
return FRAME_HEADER_VALID;
need_streaminfo:
GST_ERROR_OBJECT (flacparse, "Need STREAMINFO");
return FRAME_HEADER_INVALID;
error:
return FRAME_HEADER_INVALID;
need_more_data:
return FRAME_HEADER_MORE_DATA;
}
static gboolean
gst_flac_parse_frame_is_valid (GstFlacParse * flacparse, GstBuffer * buffer,
guint * ret)
{
const guint8 *data;
guint max, size, remaining;
guint i, search_start, search_end;
FrameHeaderCheckReturn header_ret;
guint16 block_size;
data = GST_BUFFER_DATA (buffer);
size = GST_BUFFER_SIZE (buffer);
if (size <= flacparse->min_framesize)
goto need_more;
header_ret =
gst_flac_parse_frame_header_is_valid (flacparse, data, size, TRUE,
&block_size);
if (header_ret == FRAME_HEADER_INVALID) {
*ret = 0;
return FALSE;
} else if (header_ret == FRAME_HEADER_MORE_DATA) {
goto need_more;
}
search_start = MAX (2, flacparse->min_framesize);
search_end = MIN (size, flacparse->max_framesize + 9 + 2);
search_end -= 2;
remaining = size;
for (i = search_start; i < search_end; i++, remaining--) {
if ((GST_READ_UINT16_BE (data + i) & 0xfffe) == 0xfff8) {
header_ret =
gst_flac_parse_frame_header_is_valid (flacparse, data + i, remaining,
FALSE, NULL);
if (header_ret == FRAME_HEADER_VALID) {
if (flacparse->check_frame_checksums) {
guint16 actual_crc = gst_flac_calculate_crc16 (data, i - 2);
guint16 expected_crc = GST_READ_UINT16_BE (data + i - 2);
if (actual_crc != expected_crc)
continue;
}
*ret = i;
flacparse->block_size = block_size;
return TRUE;
} else if (header_ret == FRAME_HEADER_MORE_DATA) {
goto need_more;
}
}
}
/* For the last frame check the CRC16 instead of the following
* header, which does not exist */
if (G_UNLIKELY (gst_base_parse_get_drain (GST_BASE_PARSE (flacparse)))) {
guint16 actual_crc = gst_flac_calculate_crc16 (data, size - 2);
guint16 expected_crc = GST_READ_UINT16_BE (data + size - 2);
if (actual_crc == expected_crc) {
*ret = size;
flacparse->block_size = block_size;
return TRUE;
}
}
need_more:
max = flacparse->max_framesize + 16;
if (max == 16)
max = 1 << 24;
*ret = MIN (size + 4096, max);
return FALSE;
}
static gboolean
gst_flac_parse_check_valid_frame (GstBaseParse * parse,
GstBuffer * buffer, guint * framesize, gint * skipsize)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (parse);
const guint8 *data = GST_BUFFER_DATA (buffer);
if (G_UNLIKELY (GST_BUFFER_SIZE (buffer) < 4))
return FALSE;
if (flacparse->state == GST_FLAC_PARSE_STATE_INIT) {
if (memcmp (GST_BUFFER_DATA (buffer), "fLaC", 4) == 0) {
GST_DEBUG_OBJECT (flacparse, "fLaC marker found");
*framesize = 4;
return TRUE;
} else if (data[0] == 0xff && (data[1] >> 2) == 0x3e) {
GST_DEBUG_OBJECT (flacparse, "Found headerless FLAC");
/* Minimal size of a frame header */
gst_base_parse_set_min_frame_size (GST_BASE_PARSE (flacparse), 9);
flacparse->state = GST_FLAC_PARSE_STATE_GENERATE_HEADERS;
*skipsize = 0;
return FALSE;
} else {
GST_DEBUG_OBJECT (flacparse, "fLaC marker not found");
return FALSE;
}
} else if (flacparse->state == GST_FLAC_PARSE_STATE_HEADERS) {
guint size = 4 + ((data[1] << 16) | (data[2] << 8) | (data[3]));
GST_DEBUG_OBJECT (flacparse, "Found metadata block of size %u", size);
*framesize = size;
return TRUE;
} else {
if ((GST_READ_UINT16_BE (data) & 0xfffe) == 0xfff8) {
gboolean ret;
guint next;
flacparse->offset = GST_BUFFER_OFFSET (buffer);
flacparse->blocking_strategy = 0;
flacparse->block_size = 0;
flacparse->sample_number = 0;
GST_DEBUG_OBJECT (flacparse, "Found sync code");
ret = gst_flac_parse_frame_is_valid (flacparse, buffer, &next);
if (ret) {
*framesize = next;
return TRUE;
} else {
/* If we're at EOS and the frame was not valid, drop it! */
if (G_UNLIKELY (gst_base_parse_get_drain (parse))) {
GST_WARNING_OBJECT (flacparse, "EOS");
return FALSE;
}
if (next == 0) {
} else if (next > GST_BUFFER_SIZE (buffer)) {
GST_DEBUG_OBJECT (flacparse, "Requesting %u bytes", next);
*skipsize = 0;
gst_base_parse_set_min_frame_size (parse, next);
return FALSE;
} else {
GST_ERROR_OBJECT (flacparse,
"Giving up on invalid frame (%d bytes)",
GST_BUFFER_SIZE (buffer));
return FALSE;
}
}
} else {
GstByteReader reader = GST_BYTE_READER_INIT_FROM_BUFFER (buffer);
gint off;
off =
gst_byte_reader_masked_scan_uint32 (&reader, 0xfffc0000, 0xfff80000,
0, GST_BUFFER_SIZE (buffer));
if (off > 0) {
GST_DEBUG_OBJECT (parse, "Possible sync at buffer offset %d", off);
*skipsize = off;
return FALSE;
} else {
GST_DEBUG_OBJECT (flacparse, "Sync code not found");
*skipsize = GST_BUFFER_SIZE (buffer) - 3;
return FALSE;
}
}
}
return FALSE;
}
static gboolean
gst_flac_parse_handle_streaminfo (GstFlacParse * flacparse, GstBuffer * buffer)
{
GstBitReader reader = GST_BIT_READER_INIT_FROM_BUFFER (buffer);
if (GST_BUFFER_SIZE (buffer) != 4 + 34) {
GST_ERROR_OBJECT (flacparse, "Invalid metablock size for STREAMINFO: %u",
GST_BUFFER_SIZE (buffer));
return FALSE;
}
/* Skip metadata block header */
gst_bit_reader_skip (&reader, 32);
if (!gst_bit_reader_get_bits_uint16 (&reader, &flacparse->min_blocksize, 16))
goto error;
if (flacparse->min_blocksize < 16) {
GST_ERROR_OBJECT (flacparse, "Invalid minimum block size: %u",
flacparse->min_blocksize);
return FALSE;
}
if (!gst_bit_reader_get_bits_uint16 (&reader, &flacparse->max_blocksize, 16))
goto error;
if (flacparse->max_blocksize < 16) {
GST_ERROR_OBJECT (flacparse, "Invalid maximum block size: %u",
flacparse->max_blocksize);
return FALSE;
}
if (!gst_bit_reader_get_bits_uint32 (&reader, &flacparse->min_framesize, 24))
goto error;
if (!gst_bit_reader_get_bits_uint32 (&reader, &flacparse->max_framesize, 24))
goto error;
if (!gst_bit_reader_get_bits_uint32 (&reader, &flacparse->samplerate, 20))
goto error;
if (flacparse->samplerate == 0) {
GST_ERROR_OBJECT (flacparse, "Invalid sample rate 0");
return FALSE;
}
if (!gst_bit_reader_get_bits_uint8 (&reader, &flacparse->channels, 3))
goto error;
flacparse->channels++;
if (flacparse->channels > 8) {
GST_ERROR_OBJECT (flacparse, "Invalid number of channels %u",
flacparse->channels);
return FALSE;
}
if (!gst_bit_reader_get_bits_uint8 (&reader, &flacparse->bps, 5))
goto error;
flacparse->bps++;
if (!gst_bit_reader_get_bits_uint64 (&reader, &flacparse->total_samples, 36))
goto error;
if (flacparse->total_samples)
gst_base_parse_set_duration (GST_BASE_PARSE (flacparse), GST_FORMAT_TIME,
GST_FRAMES_TO_CLOCK_TIME (flacparse->total_samples,
flacparse->samplerate), 0);
GST_DEBUG_OBJECT (flacparse, "STREAMINFO:\n"
"\tmin/max blocksize: %u/%u,\n"
"\tmin/max framesize: %u/%u,\n"
"\tsamplerate: %u,\n"
"\tchannels: %u,\n"
"\tbits per sample: %u,\n"
"\ttotal samples: %" G_GUINT64_FORMAT,
flacparse->min_blocksize, flacparse->max_blocksize,
flacparse->min_framesize, flacparse->max_framesize,
flacparse->samplerate,
flacparse->channels, flacparse->bps, flacparse->total_samples);
return TRUE;
error:
GST_ERROR_OBJECT (flacparse, "Failed to read data");
return FALSE;
}
static gboolean
gst_flac_parse_handle_vorbiscomment (GstFlacParse * flacparse,
GstBuffer * buffer)
{
flacparse->tags = gst_tag_list_from_vorbiscomment_buffer (buffer,
GST_BUFFER_DATA (buffer), 4, NULL);
if (flacparse->tags == NULL) {
GST_ERROR_OBJECT (flacparse, "Invalid vorbiscomment block");
} else if (gst_tag_list_is_empty (flacparse->tags)) {
gst_tag_list_free (flacparse->tags);
flacparse->tags = NULL;
}
return TRUE;
}
static gboolean
gst_flac_parse_handle_picture (GstFlacParse * flacparse, GstBuffer * buffer)
{
GstByteReader reader = GST_BYTE_READER_INIT_FROM_BUFFER (buffer);
const guint8 *data = GST_BUFFER_DATA (buffer);
guint32 img_len = 0, img_type = 0;
guint32 img_mimetype_len = 0, img_description_len = 0;
if (!gst_byte_reader_skip (&reader, 4))
goto error;
if (!gst_byte_reader_get_uint32_be (&reader, &img_type))
goto error;
if (!gst_byte_reader_get_uint32_be (&reader, &img_mimetype_len))
goto error;
if (!gst_byte_reader_skip (&reader, img_mimetype_len))
goto error;
if (!gst_byte_reader_get_uint32_be (&reader, &img_description_len))
goto error;
if (!gst_byte_reader_skip (&reader, img_description_len))
goto error;
if (!gst_byte_reader_skip (&reader, 4 * 4))
goto error;
if (!gst_byte_reader_get_uint32_be (&reader, &img_len))
goto error;
if (!flacparse->tags)
flacparse->tags = gst_tag_list_new ();
gst_tag_list_add_id3_image (flacparse->tags,
data + gst_byte_reader_get_pos (&reader), img_len, img_type);
if (gst_tag_list_is_empty (flacparse->tags)) {
gst_tag_list_free (flacparse->tags);
flacparse->tags = NULL;
}
return TRUE;
error:
GST_ERROR_OBJECT (flacparse, "Error reading data");
return FALSE;
}
static void
_value_array_append_buffer (GValue * array_val, GstBuffer * buf)
{
GValue value = { 0, };
g_value_init (&value, GST_TYPE_BUFFER);
/* copy buffer to avoid problems with circular refcounts */
buf = gst_buffer_copy (buf);
/* again, for good measure */
GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_IN_CAPS);
gst_value_set_buffer (&value, buf);
gst_buffer_unref (buf);
gst_value_array_append_value (array_val, &value);
g_value_unset (&value);
}
static gboolean
gst_flac_parse_handle_headers (GstFlacParse * flacparse)
{
GstBuffer *vorbiscomment = NULL;
GstBuffer *streaminfo = NULL;
GstBuffer *marker = NULL;
GValue array = { 0, };
GstCaps *caps;
GList *l;
caps = gst_caps_new_simple ("audio/x-flac",
"channels", G_TYPE_INT, flacparse->channels,
"framed", G_TYPE_BOOLEAN, TRUE,
"rate", G_TYPE_INT, flacparse->samplerate, NULL);
if (!flacparse->headers)
goto push_headers;
for (l = flacparse->headers; l; l = l->next) {
GstBuffer *header = l->data;
const guint8 *data = GST_BUFFER_DATA (header);
guint size = GST_BUFFER_SIZE (header);
GST_BUFFER_FLAG_SET (header, GST_BUFFER_FLAG_IN_CAPS);
if (size == 4 && memcmp (data, "fLaC", 4) == 0) {
marker = header;
} else if (size > 1 && (data[0] & 0x7f) == 0) {
streaminfo = header;
} else if (size > 1 && (data[0] & 0x7f) == 4) {
vorbiscomment = header;
}
}
if (marker == NULL || streaminfo == NULL || vorbiscomment == NULL) {
GST_WARNING_OBJECT (flacparse,
"missing header %p %p %p, muxing into container "
"formats may be broken", marker, streaminfo, vorbiscomment);
goto push_headers;
}
g_value_init (&array, GST_TYPE_ARRAY);
/* add marker including STREAMINFO header */
{
GstBuffer *buf;
guint16 num;
/* minus one for the marker that is merged with streaminfo here */
num = g_list_length (flacparse->headers) - 1;
buf = gst_buffer_new_and_alloc (13 + GST_BUFFER_SIZE (streaminfo));
GST_BUFFER_DATA (buf)[0] = 0x7f;
memcpy (GST_BUFFER_DATA (buf) + 1, "FLAC", 4);
GST_BUFFER_DATA (buf)[5] = 0x01; /* mapping version major */
GST_BUFFER_DATA (buf)[6] = 0x00; /* mapping version minor */
GST_BUFFER_DATA (buf)[7] = (num & 0xFF00) >> 8;
GST_BUFFER_DATA (buf)[8] = (num & 0x00FF) >> 0;
memcpy (GST_BUFFER_DATA (buf) + 9, "fLaC", 4);
memcpy (GST_BUFFER_DATA (buf) + 13, GST_BUFFER_DATA (streaminfo),
GST_BUFFER_SIZE (streaminfo));
_value_array_append_buffer (&array, buf);
gst_buffer_unref (buf);
}
/* add VORBISCOMMENT header */
_value_array_append_buffer (&array, vorbiscomment);
/* add other headers, if there are any */
for (l = flacparse->headers; l; l = l->next) {
if (GST_BUFFER_CAST (l->data) != marker &&
GST_BUFFER_CAST (l->data) != streaminfo &&
GST_BUFFER_CAST (l->data) != vorbiscomment) {
_value_array_append_buffer (&array, GST_BUFFER_CAST (l->data));
}
}
gst_structure_set_value (gst_caps_get_structure (caps, 0),
"streamheader", &array);
g_value_unset (&array);
push_headers:
gst_pad_set_caps (GST_BASE_PARSE_SRC_PAD (GST_BASE_PARSE (flacparse)), caps);
gst_caps_unref (caps);
/* push header buffers; update caps, so when we push the first buffer the
* negotiated caps will change to caps that include the streamheader field */
for (l = flacparse->headers; l != NULL; l = l->next) {
GstBuffer *buf = GST_BUFFER (l->data);
GstFlowReturn ret;
l->data = NULL;
buf = gst_buffer_make_metadata_writable (buf);
gst_buffer_set_caps (buf,
GST_PAD_CAPS (GST_BASE_PARSE_SRC_PAD (GST_BASE_PARSE (flacparse))));
ret = gst_base_parse_push_buffer (GST_BASE_PARSE (flacparse), buf);
if (ret != GST_FLOW_OK)
return FALSE;
}
g_list_free (flacparse->headers);
flacparse->headers = NULL;
return TRUE;
}
static gboolean
gst_flac_parse_generate_headers (GstFlacParse * flacparse)
{
GstBuffer *marker, *streaminfo, *vorbiscomment;
guint8 *data;
marker = gst_buffer_new_and_alloc (4);
memcpy (GST_BUFFER_DATA (marker), "fLaC", 4);
GST_BUFFER_TIMESTAMP (marker) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (marker) = GST_CLOCK_TIME_NONE;
GST_BUFFER_OFFSET (marker) = 0;
GST_BUFFER_OFFSET_END (marker) = 0;
flacparse->headers = g_list_append (flacparse->headers, marker);
streaminfo = gst_buffer_new_and_alloc (4 + 34);
data = GST_BUFFER_DATA (streaminfo);
memset (data, 0, 4 + 34);
/* metadata block header */
data[0] = 0x00; /* is_last = 0; type = 0; */
data[1] = 0x00; /* length = 34; */
data[2] = 0x00;
data[3] = 0x22;
/* streaminfo */
data[4] = (flacparse->block_size >> 8) & 0xff; /* min blocksize = blocksize; */
data[5] = (flacparse->block_size) & 0xff;
data[6] = (flacparse->block_size >> 8) & 0xff; /* max blocksize = blocksize; */
data[7] = (flacparse->block_size) & 0xff;
data[8] = 0x00; /* min framesize = 0; */
data[9] = 0x00;
data[10] = 0x00;
data[11] = 0x00; /* max framesize = 0; */
data[12] = 0x00;
data[13] = 0x00;
data[14] = (flacparse->samplerate >> 12) & 0xff;
data[15] = (flacparse->samplerate >> 4) & 0xff;
data[16] = (flacparse->samplerate >> 0) & 0xf0;
data[16] |= (flacparse->channels - 1) << 1;
data[16] |= ((flacparse->bps - 1) >> 4) & 0x01;
data[17] = (((flacparse->bps - 1)) & 0x0f) << 4;
{
gint64 duration;
GstFormat fmt = GST_FORMAT_TIME;
if (gst_pad_query_peer_duration (GST_BASE_PARSE_SINK_PAD (GST_BASE_PARSE
(flacparse)), &fmt, &duration) && fmt == GST_FORMAT_TIME) {
duration = GST_CLOCK_TIME_TO_FRAMES (duration, flacparse->samplerate);
data[17] |= (duration >> 32) & 0xff;
data[18] |= (duration >> 24) & 0xff;
data[19] |= (duration >> 16) & 0xff;
data[20] |= (duration >> 8) & 0xff;
data[21] |= (duration >> 0) & 0xff;
}
}
/* MD5 = 0; */
GST_BUFFER_TIMESTAMP (streaminfo) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (streaminfo) = GST_CLOCK_TIME_NONE;
GST_BUFFER_OFFSET (streaminfo) = 0;
GST_BUFFER_OFFSET_END (streaminfo) = 0;
flacparse->headers = g_list_append (flacparse->headers, streaminfo);
/* empty vorbiscomment */
{
GstTagList *taglist = gst_tag_list_new ();
guchar header[4];
guint size;
header[0] = 0x84; /* is_last = 1; type = 4; */
vorbiscomment =
gst_tag_list_to_vorbiscomment_buffer (taglist, header,
sizeof (header), NULL);
gst_tag_list_free (taglist);
/* Get rid of framing bit */
if (GST_BUFFER_DATA (vorbiscomment)[GST_BUFFER_SIZE (vorbiscomment) -
1] == 1) {
GstBuffer *sub;
sub =
gst_buffer_create_sub (vorbiscomment, 0,
GST_BUFFER_SIZE (vorbiscomment) - 1);
gst_buffer_unref (vorbiscomment);
vorbiscomment = sub;
}
size = GST_BUFFER_SIZE (vorbiscomment) - 4;
GST_BUFFER_DATA (vorbiscomment)[1] = ((size & 0xFF0000) >> 16);
GST_BUFFER_DATA (vorbiscomment)[2] = ((size & 0x00FF00) >> 8);
GST_BUFFER_DATA (vorbiscomment)[3] = (size & 0x0000FF);
GST_BUFFER_TIMESTAMP (vorbiscomment) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (vorbiscomment) = GST_CLOCK_TIME_NONE;
GST_BUFFER_OFFSET (vorbiscomment) = 0;
GST_BUFFER_OFFSET_END (vorbiscomment) = 0;
flacparse->headers = g_list_append (flacparse->headers, vorbiscomment);
}
return TRUE;
}
static GstFlowReturn
gst_flac_parse_parse_frame (GstBaseParse * parse, GstBuffer * buffer)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (parse);
const guint8 *data = GST_BUFFER_DATA (buffer);
if (flacparse->state == GST_FLAC_PARSE_STATE_INIT) {
GST_BUFFER_TIMESTAMP (buffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_OFFSET (buffer) = 0;
GST_BUFFER_OFFSET_END (buffer) = 0;
/* 32 bits metadata block */
gst_base_parse_set_min_frame_size (GST_BASE_PARSE (flacparse), 4);
flacparse->state = GST_FLAC_PARSE_STATE_HEADERS;
flacparse->headers =
g_list_append (flacparse->headers, gst_buffer_ref (buffer));
return GST_BASE_PARSE_FLOW_DROPPED;
} else if (flacparse->state == GST_FLAC_PARSE_STATE_HEADERS) {
gboolean is_last = ((data[0] & 0x80) == 0x80);
guint type = (data[0] & 0x7F);
if (type == 127) {
GST_WARNING_OBJECT (flacparse, "Invalid metadata block type");
return GST_BASE_PARSE_FLOW_DROPPED;
}
GST_DEBUG_OBJECT (flacparse, "Handling metadata block of type %u", type);
switch (type) {
case 0: /* STREAMINFO */
if (!gst_flac_parse_handle_streaminfo (flacparse, buffer))
return GST_FLOW_ERROR;
break;
case 3: /* SEEKTABLE */
/* TODO: handle seektables */
break;
case 4: /* VORBIS_COMMENT */
if (!gst_flac_parse_handle_vorbiscomment (flacparse, buffer))
return GST_FLOW_ERROR;
break;
case 6: /* PICTURE */
if (!gst_flac_parse_handle_picture (flacparse, buffer))
return GST_FLOW_ERROR;
break;
case 1: /* PADDING */
case 2: /* APPLICATION */
case 5: /* CUESHEET */
default: /* RESERVED */
break;
}
GST_BUFFER_TIMESTAMP (buffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_OFFSET (buffer) = 0;
GST_BUFFER_OFFSET_END (buffer) = 0;
if (is_last) {
flacparse->headers =
g_list_append (flacparse->headers, gst_buffer_ref (buffer));
if (!gst_flac_parse_handle_headers (flacparse))
return GST_FLOW_ERROR;
/* Minimal size of a frame header */
gst_base_parse_set_min_frame_size (GST_BASE_PARSE (flacparse), MAX (9,
flacparse->min_framesize));
flacparse->state = GST_FLAC_PARSE_STATE_DATA;
/* DROPPED because we pushed all headers manually already */
return GST_BASE_PARSE_FLOW_DROPPED;
} else {
flacparse->headers =
g_list_append (flacparse->headers, gst_buffer_ref (buffer));
return GST_BASE_PARSE_FLOW_DROPPED;
}
} else {
if (flacparse->offset != GST_BUFFER_OFFSET (buffer)) {
FrameHeaderCheckReturn ret;
flacparse->offset = GST_BUFFER_OFFSET (buffer);
ret =
gst_flac_parse_frame_header_is_valid (flacparse,
GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer), TRUE, NULL);
if (ret != FRAME_HEADER_VALID) {
GST_ERROR_OBJECT (flacparse,
"Baseclass didn't provide a complete frame");
return GST_FLOW_ERROR;
}
}
if (flacparse->block_size == 0) {
GST_ERROR_OBJECT (flacparse, "Unparsed frame");
return GST_FLOW_ERROR;
}
if (flacparse->state == GST_FLAC_PARSE_STATE_GENERATE_HEADERS) {
if (flacparse->blocking_strategy == 1) {
GST_WARNING_OBJECT (flacparse,
"Generating headers for variable blocksize streams not supported");
if (!gst_flac_parse_handle_headers (flacparse))
return GST_FLOW_ERROR;
} else {
GST_DEBUG_OBJECT (flacparse, "Generating headers");
if (!gst_flac_parse_generate_headers (flacparse))
return GST_FLOW_ERROR;
if (!gst_flac_parse_handle_headers (flacparse))
return GST_FLOW_ERROR;
}
flacparse->state = GST_FLAC_PARSE_STATE_DATA;
}
/* also cater for oggmux metadata */
if (flacparse->blocking_strategy == 0) {
GST_BUFFER_TIMESTAMP (buffer) =
gst_util_uint64_scale (flacparse->sample_number,
flacparse->block_size * GST_SECOND, flacparse->samplerate);
GST_BUFFER_OFFSET_END (buffer) =
flacparse->sample_number * flacparse->block_size +
flacparse->block_size;
} else {
GST_BUFFER_TIMESTAMP (buffer) =
gst_util_uint64_scale (flacparse->sample_number, GST_SECOND,
flacparse->samplerate);
GST_BUFFER_OFFSET_END (buffer) =
flacparse->sample_number + flacparse->block_size;
}
GST_BUFFER_DURATION (buffer) =
GST_FRAMES_TO_CLOCK_TIME (flacparse->block_size, flacparse->samplerate);
GST_BUFFER_OFFSET (buffer) =
GST_BUFFER_TIMESTAMP (buffer) + GST_BUFFER_DURATION (buffer);
/* Minimal size of a frame header */
gst_base_parse_set_min_frame_size (GST_BASE_PARSE (flacparse), MAX (9,
flacparse->min_framesize));
flacparse->offset = -1;
flacparse->blocking_strategy = 0;
flacparse->block_size = 0;
flacparse->sample_number = 0;
return GST_FLOW_OK;
}
}
static gint
gst_flac_parse_get_frame_overhead (GstBaseParse * parse, GstBuffer * buffer)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (parse);
if (flacparse->state != GST_FLAC_PARSE_STATE_DATA)
return -1;
else
/* To simplify, we just assume that it's a fixed size header and ignore
* subframe headers. The first could lead us to being off by 88 bits and
* the second even less, so the total inaccuracy is negligible. */
return 7;
}
static GstFlowReturn
gst_flac_parse_pre_push_buffer (GstBaseParse * parse, GstBuffer * buf)
{
GstFlacParse *flacparse = GST_FLAC_PARSE (parse);
/* Push tags */
if (flacparse->tags) {
gst_element_found_tags (GST_ELEMENT (flacparse), flacparse->tags);
flacparse->tags = NULL;
}
return GST_FLOW_OK;
}