gstreamer/gst/audioparsers/gstdcaparse.c
2010-12-03 18:23:14 +01:00

414 lines
13 KiB
C

/* GStreamer DCA parser
* Copyright (C) 2010 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.
*/
/**
* SECTION:element-dcaparse
* @short_description: DCA (DTS Coherent Acoustics) parser
* @see_also: #GstAmrParse, #GstAACParse, #GstAc3Parse
*
* This is a DCA (DTS Coherent Acoustics) parser.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch filesrc location=abc.dts ! dcaparse ! dtsdec ! audioresample ! audioconvert ! autoaudiosink
* ]|
* </refsect2>
*/
/* TODO:
* - should accept framed and unframed input (needs decodebin fixes first)
* - seeking in raw .dts files doesn't seem to work, but duration estimate ok
*
* - if frames have 'odd' durations, the frame durations (plus timestamps)
* aren't adjusted up occasionally to make up for rounding error gaps.
* (e.g. if 512 samples per frame @ 48kHz = 10.666666667 ms/frame)
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "gstdcaparse.h"
#include <gst/base/gstbytereader.h>
#include <gst/base/gstbitreader.h>
GST_DEBUG_CATEGORY_STATIC (dca_parse_debug);
#define GST_CAT_DEFAULT dca_parse_debug
static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-dts, framed = (boolean) true, "
" channels = (int) [ 1, 8 ], rate = (int) [ 8000, 192000 ]"));
static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-dts, framed = (boolean) false"));
static void gst_dca_parse_finalize (GObject * object);
static gboolean gst_dca_parse_start (GstBaseParse * parse);
static gboolean gst_dca_parse_stop (GstBaseParse * parse);
static gboolean gst_dca_parse_check_valid_frame (GstBaseParse * parse,
GstBuffer * buffer, guint * size, gint * skipsize);
static GstFlowReturn gst_dca_parse_parse_frame (GstBaseParse * parse,
GstBuffer * buf);
GST_BOILERPLATE (GstDcaParse, gst_dca_parse, GstBaseParse, GST_TYPE_BASE_PARSE);
static void
gst_dca_parse_base_init (gpointer klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_template));
gst_element_class_set_details_simple (element_class,
"DTS Coherent Acoustics audio stream parser", "Codec/Parser/Audio",
"DCA parser", "Tim-Philipp Müller <tim centricular net>");
}
static void
gst_dca_parse_class_init (GstDcaParseClass * klass)
{
GstBaseParseClass *parse_class = GST_BASE_PARSE_CLASS (klass);
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GST_DEBUG_CATEGORY_INIT (dca_parse_debug, "dcaparse", 0,
"DCA audio stream parser");
object_class->finalize = gst_dca_parse_finalize;
parse_class->start = GST_DEBUG_FUNCPTR (gst_dca_parse_start);
parse_class->stop = GST_DEBUG_FUNCPTR (gst_dca_parse_stop);
parse_class->check_valid_frame =
GST_DEBUG_FUNCPTR (gst_dca_parse_check_valid_frame);
parse_class->parse_frame = GST_DEBUG_FUNCPTR (gst_dca_parse_parse_frame);
}
static void
gst_dca_parse_reset (GstDcaParse * dcaparse)
{
dcaparse->channels = -1;
dcaparse->rate = -1;
dcaparse->last_sync = 0;
}
static void
gst_dca_parse_init (GstDcaParse * dcaparse, GstDcaParseClass * klass)
{
gst_base_parse_set_min_frame_size (GST_BASE_PARSE (dcaparse),
DCA_MIN_FRAMESIZE);
gst_dca_parse_reset (dcaparse);
}
static void
gst_dca_parse_finalize (GObject * object)
{
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static gboolean
gst_dca_parse_start (GstBaseParse * parse)
{
GstDcaParse *dcaparse = GST_DCA_PARSE (parse);
GST_DEBUG_OBJECT (parse, "starting");
gst_dca_parse_reset (dcaparse);
return TRUE;
}
static gboolean
gst_dca_parse_stop (GstBaseParse * parse)
{
GST_DEBUG_OBJECT (parse, "stopping");
return TRUE;
}
static gboolean
gst_dca_parse_parse_header (GstDcaParse * dcaparse,
const GstByteReader * reader, guint * frame_size,
guint * sample_rate, guint * channels, guint * samples)
{
static const int sample_rates[16] = { 0, 8000, 16000, 32000, 0, 0, 11025,
22050, 44100, 0, 0, 12000, 24000, 48000, 96000, 192000
};
static const guint8 channels_table[16] = { 1, 2, 2, 2, 2, 3, 3, 4, 4, 5,
6, 6, 6, 7, 8, 8
};
GstByteReader r = *reader;
guint16 hdr[8];
guint32 marker;
guint num_blocks, samples_per_block, chans, lfe, i;
if (gst_byte_reader_get_remaining (&r) < (4 + sizeof (hdr)))
return FALSE;
marker = gst_byte_reader_peek_uint32_be_unchecked (&r);
/* raw big endian or 14-bit big endian */
if (marker == 0x7FFE8001 || marker == 0x1FFFE800) {
for (i = 0; i < G_N_ELEMENTS (hdr); ++i)
hdr[i] = gst_byte_reader_get_uint16_be_unchecked (&r);
} else
/* raw little endian or 14-bit little endian */
if (marker == 0xFE7F0180 || marker == 0xFF1F00E8) {
for (i = 0; i < G_N_ELEMENTS (hdr); ++i)
hdr[i] = gst_byte_reader_get_uint16_le_unchecked (&r);
} else {
return FALSE;
}
GST_LOG_OBJECT (dcaparse, "dts sync marker 0x%08x at offset %u", marker,
gst_byte_reader_get_pos (reader));
/* 14-bit mode */
if (marker == 0x1FFFE800 || marker == 0xFF1F00E8) {
if ((hdr[2] & 0xFFF0) != 0x07F0)
return FALSE;
/* discard top 2 bits (2 void), shift in 2 */
hdr[0] = (hdr[0] << 2) | ((hdr[1] >> 12) & 0x0003);
/* discard top 4 bits (2 void, 2 shifted into hdr[0]), shift in 4 etc. */
hdr[1] = (hdr[1] << 4) | ((hdr[2] >> 10) & 0x000F);
hdr[2] = (hdr[2] << 6) | ((hdr[3] >> 8) & 0x003F);
hdr[3] = (hdr[3] << 8) | ((hdr[4] >> 6) & 0x00FF);
hdr[4] = (hdr[4] << 10) | ((hdr[5] >> 4) & 0x03FF);
hdr[5] = (hdr[5] << 12) | ((hdr[6] >> 2) & 0x0FFF);
hdr[6] = (hdr[6] << 14) | ((hdr[7] >> 0) & 0x3FFF);
g_assert (hdr[0] == 0x7FFE && hdr[1] == 0x8001);
}
GST_LOG_OBJECT (dcaparse, "frame header: %04x%04x%04x%04x",
hdr[2], hdr[3], hdr[4], hdr[5]);
samples_per_block = ((hdr[2] >> 10) & 0x1f) + 1;
num_blocks = ((hdr[2] >> 2) & 0x7F) + 1;
*frame_size = (((hdr[2] & 0x03) << 12) | (hdr[3] >> 4)) + 1;
chans = ((hdr[3] & 0x0F) << 2) | (hdr[4] >> 14);
*sample_rate = sample_rates[(hdr[4] >> 10) & 0x0F];
lfe = (hdr[5] >> 9) & 0x03;
GST_TRACE_OBJECT (dcaparse, "frame size %u, num_blocks %u, rate %u, "
"samples per block %u", *frame_size, num_blocks, *sample_rate,
samples_per_block);
if (num_blocks < 6 || *frame_size < 96 || *sample_rate == 0)
return FALSE;
if (marker == 0x1FFFE800 || marker == 0xFF1F00E8)
*frame_size = (*frame_size * 16) / 14; /* FIXME: round up? */
if (chans < G_N_ELEMENTS (channels_table))
*channels = channels_table[chans] + ((lfe) ? 1 : 0);
else
*channels = 0;
*samples = num_blocks * samples_per_block;
GST_TRACE_OBJECT (dcaparse, "frame size %u, channels %u, rate %u, samples %u",
*frame_size, *channels, *sample_rate, *samples);
return TRUE;
}
static gint
gst_dca_parse_find_sync (GstDcaParse * dcaparse, GstByteReader * reader,
const GstBuffer * buf, guint32 * sync)
{
guint32 best_sync = 0;
guint best_offset = G_MAXUINT;
gint off;
/* FIXME: verify syncs via _parse_header() here already */
/* Raw big endian */
off = gst_byte_reader_masked_scan_uint32 (reader, 0xffffffff, 0xfe7f0180,
0, GST_BUFFER_SIZE (buf));
if (off >= 0 && off < best_offset) {
best_offset = off;
best_sync = 0xfe7f0180;
}
/* Raw little endian */
off = gst_byte_reader_masked_scan_uint32 (reader, 0xffffffff, 0x7ffe8001,
0, GST_BUFFER_SIZE (buf));
if (off >= 0 && off < best_offset) {
best_offset = off;
best_sync = 0x7ffe8001;
}
/* FIXME: check next 2 bytes as well for 14-bit formats (but then don't
* forget to adjust the *skipsize= in _check_valid_frame() */
/* 14-bit big endian */
off = gst_byte_reader_masked_scan_uint32 (reader, 0xffffffff, 0xfe7f0180,
0, GST_BUFFER_SIZE (buf));
if (off >= 0 && off < best_offset) {
best_offset = off;
best_sync = 0xfe7f0180;
}
/* 14-bit little endian */
off = gst_byte_reader_masked_scan_uint32 (reader, 0xffffffff, 0x1fffe800,
0, GST_BUFFER_SIZE (buf));
if (off >= 0 && off < best_offset) {
best_offset = off;
best_sync = 0x1fffe800;
}
if (best_offset == G_MAXUINT)
return -1;
*sync = best_sync;
return best_offset;
}
static gboolean
gst_dca_parse_check_valid_frame (GstBaseParse * parse, GstBuffer * buf,
guint * framesize, gint * skipsize)
{
GstByteReader r = GST_BYTE_READER_INIT_FROM_BUFFER (buf);
GstDcaParse *dcaparse = GST_DCA_PARSE (parse);
gboolean parser_draining;
gboolean parser_in_sync;
guint32 sync = 0;
guint size, rate, chans, samples;
gint off = -1;
if (G_UNLIKELY (GST_BUFFER_SIZE (buf) < 16))
return FALSE;
parser_in_sync = gst_base_parse_get_sync (parse);
if (G_LIKELY (parser_in_sync && dcaparse->last_sync != 0)) {
off = gst_byte_reader_masked_scan_uint32 (&r, 0xffffffff,
dcaparse->last_sync, 0, GST_BUFFER_SIZE (buf));
}
if (G_UNLIKELY (off < 0)) {
off = gst_dca_parse_find_sync (dcaparse, &r, buf, &sync);
}
/* didn't find anything that looks like a sync word, skip */
if (off < 0) {
*skipsize = GST_BUFFER_SIZE (buf) - 3;
return FALSE;
}
GST_LOG_OBJECT (parse, "possible sync %08x at buffer offset %d", sync, off);
/* possible frame header, but not at offset 0? skip bytes before sync */
if (off > 0) {
*skipsize = off;
return FALSE;
}
/* make sure the values in the frame header look sane */
if (!gst_dca_parse_parse_header (dcaparse, &r, &size, &rate, &chans,
&samples)) {
*skipsize = 4;
return FALSE;
}
GST_LOG_OBJECT (parse, "got frame, sync %08x, size %u, rate %d, channels %d",
sync, size, rate, chans);
*framesize = size;
dcaparse->last_sync = sync;
parser_draining = gst_base_parse_get_drain (parse);
if (!parser_in_sync && !parser_draining) {
/* check for second frame to be sure */
GST_DEBUG_OBJECT (dcaparse, "resyncing; checking next frame syncword");
if (GST_BUFFER_SIZE (buf) >= (size + 16)) {
guint s2, r2, c2, n2;
GST_MEMDUMP ("buf", GST_BUFFER_DATA (buf), size + 16);
gst_byte_reader_init_from_buffer (&r, buf);
gst_byte_reader_skip_unchecked (&r, size);
if (!gst_dca_parse_parse_header (dcaparse, &r, &s2, &r2, &c2, &n2)) {
GST_DEBUG_OBJECT (dcaparse, "didn't find second syncword");
*skipsize = 4;
return FALSE;
}
/* ok, got sync now, let's assume constant frame size */
gst_base_parse_set_min_frame_size (parse, size);
} else {
/* FIXME: baseparse always seems to hand us buffers of min_frame_size
* bytes, which is unhelpful here */
GST_LOG_OBJECT (dcaparse, "next sync out of reach (%u < %u)",
GST_BUFFER_SIZE (buf), size + 16);
/* *skipsize = 0; */
/* return FALSE; */
}
}
return TRUE;
}
static GstFlowReturn
gst_dca_parse_parse_frame (GstBaseParse * parse, GstBuffer * buf)
{
GstByteReader r = GST_BYTE_READER_INIT_FROM_BUFFER (buf);
GstDcaParse *dcaparse = GST_DCA_PARSE (parse);
guint size, rate, chans, samples;
if (!gst_dca_parse_parse_header (dcaparse, &r, &size, &rate, &chans,
&samples))
goto broken_header;
if (G_UNLIKELY (dcaparse->rate != rate || dcaparse->channels != chans)) {
GstCaps *caps;
caps = gst_caps_new_simple ("audio/x-dts",
"framed", G_TYPE_BOOLEAN, TRUE,
"rate", G_TYPE_INT, rate, "channels", G_TYPE_INT, chans, NULL);
gst_buffer_set_caps (buf, caps);
gst_pad_set_caps (GST_BASE_PARSE_SRC_PAD (parse), caps);
gst_caps_unref (caps);
dcaparse->rate = rate;
dcaparse->channels = chans;
gst_base_parse_set_frame_props (parse, rate, samples, 0, 0);
}
return GST_FLOW_OK;
/* ERRORS */
broken_header:
{
/* this really shouldn't ever happen */
GST_ELEMENT_ERROR (parse, STREAM, DECODE, (NULL), (NULL));
return GST_FLOW_ERROR;
}
}