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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /media/ffvpx/libavcodec/mpegaudiodecheader.h
parentInitial commit. (diff)
downloadfirefox-esr-upstream.tar.xz
firefox-esr-upstream.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--media/ffvpx/libavcodec/mpegaudiodecheader.h81
1 files changed, 81 insertions, 0 deletions
diff --git a/media/ffvpx/libavcodec/mpegaudiodecheader.h b/media/ffvpx/libavcodec/mpegaudiodecheader.h
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index 0000000000..ed5d1f3b33
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+++ b/media/ffvpx/libavcodec/mpegaudiodecheader.h
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+/*
+ * MPEG Audio header decoder
+ * Copyright (c) 2001, 2002 Fabrice Bellard
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * MPEG Audio header decoder.
+ */
+
+#ifndef AVCODEC_MPEGAUDIODECHEADER_H
+#define AVCODEC_MPEGAUDIODECHEADER_H
+
+#include <stdint.h>
+#include "codec_id.h"
+
+#define MP3_MASK 0xFFFE0CCF
+
+#define MPA_DECODE_HEADER \
+ int frame_size; \
+ int error_protection; \
+ int layer; \
+ int sample_rate; \
+ int sample_rate_index; /* between 0 and 8 */ \
+ int bit_rate; \
+ int nb_channels; \
+ int mode; \
+ int mode_ext; \
+ int lsf;
+
+typedef struct MPADecodeHeader {
+ MPA_DECODE_HEADER
+} MPADecodeHeader;
+
+/* header decoding. MUST check the header before because no
+ consistency check is done there. Return 1 if free format found and
+ that the frame size must be computed externally */
+int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header);
+
+/* useful helper to get MPEG audio stream info. Return -1 if error in
+ header, otherwise the coded frame size in bytes */
+int ff_mpa_decode_header(uint32_t head, int *sample_rate,
+ int *channels, int *frame_size, int *bitrate, enum AVCodecID *codec_id);
+
+/* fast header check for resync */
+static inline int ff_mpa_check_header(uint32_t header){
+ /* header */
+ if ((header & 0xffe00000) != 0xffe00000)
+ return -1;
+ /* version check */
+ if ((header & (3<<19)) == 1<<19)
+ return -1;
+ /* layer check */
+ if ((header & (3<<17)) == 0)
+ return -1;
+ /* bit rate */
+ if ((header & (0xf<<12)) == 0xf<<12)
+ return -1;
+ /* frequency */
+ if ((header & (3<<10)) == 3<<10)
+ return -1;
+ return 0;
+}
+
+#endif /* AVCODEC_MPEGAUDIODECHEADER_H */