mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-12-30 20:20:38 +00:00
99947d0592
GstBitWriter provides a bit writer that can write any number of bits to a pre-allocated memory buffer. Helper functions are also provided to write any number of bits from 8, 16, 32 and 64 bit variables. Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
278 lines
6.8 KiB
C
278 lines
6.8 KiB
C
/*
|
|
* gstbitwriter.c - bitstream writer
|
|
*
|
|
* Copyright (C) 2013 Intel Corporation
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public License
|
|
* as published by the Free Software Foundation; either version 2.1
|
|
* 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
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free
|
|
* Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
|
|
* Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#define GST_BIT_WRITER_DISABLE_INLINES
|
|
|
|
#include "gstbitwriter.h"
|
|
|
|
/**
|
|
* gst_bit_writer_init:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @reserved_bits: reserved bits to allocate data
|
|
*
|
|
* Initializes a #GstBitWriter instance and allocate @reserved_bits
|
|
* data inside.
|
|
*
|
|
* Cleanup function: gst_bit_writer_clear
|
|
*/
|
|
void
|
|
gst_bit_writer_init (GstBitWriter * bitwriter, guint32 reserved_bits)
|
|
{
|
|
bitwriter->bit_size = 0;
|
|
bitwriter->data = NULL;
|
|
bitwriter->bit_capacity = 0;
|
|
bitwriter->auto_grow = TRUE;
|
|
if (reserved_bits)
|
|
_gst_bit_writer_check_space (bitwriter, reserved_bits);
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_init_fill:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @data: allocated data
|
|
* @bits: size of allocated @data in bits
|
|
*
|
|
* Initializes a #GstBitWriter instance with alocated @data and @bit outside.
|
|
*
|
|
* Cleanup function: gst_bit_writer_clear
|
|
*/
|
|
void
|
|
gst_bit_writer_init_fill (GstBitWriter * bitwriter, guint8 * data, guint bits)
|
|
{
|
|
bitwriter->bit_size = 0;
|
|
bitwriter->data = data;
|
|
bitwriter->bit_capacity = bits;
|
|
bitwriter->auto_grow = FALSE;
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_clear:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @free_data: flag to free #GstBitWriter allocated data
|
|
*
|
|
* Clear a #GstBitWriter instance and destroy allocated data inside
|
|
* if @free_data is %TRUE.
|
|
*/
|
|
void
|
|
gst_bit_writer_clear (GstBitWriter * bitwriter, gboolean free_data)
|
|
{
|
|
if (bitwriter->auto_grow && bitwriter->data && free_data)
|
|
g_free (bitwriter->data);
|
|
|
|
bitwriter->data = NULL;
|
|
bitwriter->bit_size = 0;
|
|
bitwriter->bit_capacity = 0;
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_new:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @reserved_bits: reserved bits to allocate data
|
|
*
|
|
* Create a #GstBitWriter instance and allocate @reserved_bits data inside.
|
|
*
|
|
* Free-function: gst_bit_writer_free
|
|
*
|
|
* Returns: a new #GstBitWriter instance
|
|
*/
|
|
GstBitWriter *
|
|
gst_bit_writer_new (guint32 reserved_bits)
|
|
{
|
|
GstBitWriter *ret = g_slice_new0 (GstBitWriter);
|
|
|
|
gst_bit_writer_init (ret, reserved_bits);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_new_fill:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @data: allocated data
|
|
* @bits: size of allocated @data in bits
|
|
*
|
|
* Create a #GstBitWriter instance with allocated @data and @bit outside.
|
|
*
|
|
* Free-function: gst_bit_writer_free
|
|
*
|
|
* Returns: a new #GstBitWriter instance
|
|
*/
|
|
GstBitWriter *
|
|
gst_bit_writer_new_fill (guint8 * data, guint bits)
|
|
{
|
|
GstBitWriter *ret = g_slice_new0 (GstBitWriter);
|
|
|
|
gst_bit_writer_init_fill (ret, data, bits);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_free:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @free_data: flag to free @data which is allocated inside
|
|
*
|
|
* Clear a #GstBitWriter instance and destroy allocated data inside if
|
|
* @free_data is %TRUE
|
|
*/
|
|
void
|
|
gst_bit_writer_free (GstBitWriter * writer, gboolean free_data)
|
|
{
|
|
g_return_if_fail (writer != NULL);
|
|
|
|
gst_bit_writer_clear (writer, free_data);
|
|
|
|
g_slice_free (GstBitWriter, writer);
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_get_size:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
*
|
|
* Get size of written @data
|
|
*
|
|
* Returns: size of bits written in @data
|
|
*/
|
|
guint
|
|
gst_bit_writer_get_size (GstBitWriter * bitwriter)
|
|
{
|
|
return _gst_bit_writer_get_size_inline (bitwriter);
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_get_data:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
*
|
|
* Get written @data pointer
|
|
*
|
|
* Returns: @data pointer
|
|
*/
|
|
guint8 *
|
|
gst_bit_writer_get_data (GstBitWriter * bitwriter)
|
|
{
|
|
return _gst_bit_writer_get_data_inline (bitwriter);
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_get_data:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @pos: new position of data end
|
|
*
|
|
* Set the new postion of data end which should be the new size of @data.
|
|
*
|
|
* Returns: %TRUE if successful, %FALSE otherwise
|
|
*/
|
|
gboolean
|
|
gst_bit_writer_set_pos (GstBitWriter * bitwriter, guint pos)
|
|
{
|
|
return _gst_bit_writer_set_pos_inline (bitwriter, pos);
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_put_bits_uint8:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @value: value of #guint8 to write
|
|
* @nbits: number of bits to write
|
|
*
|
|
* Write @nbits bits of @value to #GstBitWriter.
|
|
*
|
|
* Returns: %TRUE if successful, %FALSE otherwise.
|
|
*/
|
|
|
|
/**
|
|
* gst_bit_writer_put_bits_uint16:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @value: value of #guint16 to write
|
|
* @nbits: number of bits to write
|
|
*
|
|
* Write @nbits bits of @value to #GstBitWriter.
|
|
*
|
|
* Returns: %TRUE if successful, %FALSE otherwise.
|
|
*/
|
|
|
|
/**
|
|
* gst_bit_writer_put_bits_uint32:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @value: value of #guint32 to write
|
|
* @nbits: number of bits to write
|
|
*
|
|
* Write @nbits bits of @value to #GstBitWriter.
|
|
*
|
|
* Returns: %TRUE if successful, %FALSE otherwise.
|
|
*/
|
|
|
|
/**
|
|
* gst_bit_writer_put_bits_uint64:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @value: value of #guint64 to write
|
|
* @nbits: number of bits to write
|
|
*
|
|
* Write @nbits bits of @value to #GstBitWriter.
|
|
*
|
|
* Returns: %TRUE if successful, %FALSE otherwise.
|
|
*/
|
|
|
|
#define GST_BIT_WRITER_WRITE_BITS(bits) \
|
|
gboolean \
|
|
gst_bit_writer_put_bits_uint##bits (GstBitWriter *bitwriter, guint##bits value, guint nbits) \
|
|
{ \
|
|
return _gst_bit_writer_put_bits_uint##bits##_inline (bitwriter, value, nbits); \
|
|
}
|
|
|
|
GST_BIT_WRITER_WRITE_BITS (8)
|
|
GST_BIT_WRITER_WRITE_BITS (16)
|
|
GST_BIT_WRITER_WRITE_BITS (32)
|
|
GST_BIT_WRITER_WRITE_BITS (64)
|
|
|
|
#undef GST_BIT_WRITER_WRITE_BITS
|
|
|
|
/**
|
|
* gst_bit_writer_put_bytes:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @data: pointer of data to write
|
|
* @nbytes: number of bytes to write
|
|
*
|
|
* Write @nbytes bytes of @data to #GstBitWriter.
|
|
*
|
|
* Returns: %TRUE if successful, %FALSE otherwise.
|
|
*/
|
|
gboolean
|
|
gst_bit_writer_put_bytes (GstBitWriter * bitwriter,
|
|
const guint8 * data, guint nbytes)
|
|
{
|
|
return _gst_bit_writer_put_bytes_inline (bitwriter, data, nbytes);
|
|
}
|
|
|
|
/**
|
|
* gst_bit_writer_align_bytes:
|
|
* @bitwriter: a #GstBitWriter instance
|
|
* @trailing_bit: trailing bits of last byte, 0 or 1
|
|
*
|
|
* Write trailing bit to align last byte of @data. @trailing_bit can
|
|
* only be 1 or 0.
|
|
*
|
|
* Returns: %TRUE if successful, %FALSE otherwise.
|
|
*/
|
|
gboolean
|
|
gst_bit_writer_align_bytes (GstBitWriter * bitwriter, guint8 trailing_bit)
|
|
{
|
|
return _gst_bit_writer_align_bytes_inline (bitwriter, trailing_bit);
|
|
}
|