linux/drivers/media/platform/chips-media/coda/coda-mpeg2.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Coda multi-standard codec IP - MPEG-2 helper functions
 *
 * Copyright (C) 2019 Pengutronix, Philipp Zabel
 */

#include <linux/kernel.h>
#include <linux/videodev2.h>
#include "coda.h"

int coda_mpeg2_profile(int profile_idc)
{ … }

int coda_mpeg2_level(int level_idc)
{ … }

/*
 * Check if the buffer starts with the MPEG-2 sequence header (with or without
 * quantization matrix) and extension header, for example:
 *
 *   00 00 01 b3 2d 01 e0 34 08 8b a3 81
 *               10 11 11 12 12 12 13 13 13 13 14 14 14 14 14 15
 *               15 15 15 15 15 16 16 16 16 16 16 16 17 17 17 17
 *               17 17 17 17 18 18 18 19 18 18 18 19 1a 1a 1a 1a
 *               19 1b 1b 1b 1b 1b 1c 1c 1c 1c 1e 1e 1e 1f 1f 21
 *   00 00 01 b5 14 8a 00 01 00 00
 *
 * or:
 *
 *   00 00 01 b3 08 00 40 15 ff ff e0 28
 *   00 00 01 b5 14 8a 00 01 00 00
 *
 * Returns the detected header size in bytes or 0.
 */
u32 coda_mpeg2_parse_headers(struct coda_ctx *ctx, u8 *buf, u32 size)
{ … }