mirror of
https://github.com/hrydgard/ppsspp.git
synced 2026-11-01 20:18:15 +01:00
Henrik RydgårdandClaude Opus 5.5
d0e3141f43
The ffmpeg submodule held prebuilt libraries for every platform next to the sources (about 1.5 GB checked out), and nothing uses those any more. Only the needed sources are copied in, from the submodule's commit, along with every header and template they include. The path is new, so checking out commits on either side of this works. It's also cut down to what PPSSPP uses: the H.264, AAC, MP3, ATRAC3 and ATRAC3+ decoders, the H.264 parser, the demuxers as before, and the FFV1 encoder, AVI muxer and file protocol for AVI dumping. config.h takes its CONFIG_ values from FFmpeg 3.0.2's own configure run with just those enabled. The raw H.264 demuxer stays even though nothing opens raw H.264: probing PSMF data uses it to identify the video stream's codec, which otherwise comes out as none. On top of that: - The files nothing links (configure would build them, but they're never pulled out of the static library, going by the GCC link map) are left out: mostly libavutil's crypto and hashing and the alternative DCT/IDCT/FFT versions. - libswresample isn't built, now that nothing uses it. - The H.264 decoder only does 8-bit video, which is all the PSP has. The SPS parser rejects any other bit depth, and the DSP files no longer build their 9- to 16-bit variants, which the linker kept because the init functions pick one by bit depth at run time. That's 160 files to compile instead of 277, and 391 of FFmpeg's vendored, about 5.8 MB. The README in ext/ffmpeg has what was done, the PPSSPP patches in the copy, how to add a component, and the tradeoffs. Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
83 lines
2.6 KiB
C
83 lines
2.6 KiB
C
/*
|
|
* 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 "avcodec.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 infos. 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);
|
|
|
|
#if LIBAVCODEC_VERSION_MAJOR < 58
|
|
int avpriv_mpa_decode_header(AVCodecContext *avctx, uint32_t head, int *sample_rate, int *channels, int *frame_size, int *bitrate);
|
|
int avpriv_mpa_decode_header2(uint32_t head, int *sample_rate, int *channels, int *frame_size, int *bitrate, enum AVCodecID *codec_id);
|
|
#endif
|
|
|
|
/* fast header check for resync */
|
|
static inline int ff_mpa_check_header(uint32_t header){
|
|
/* header */
|
|
if ((header & 0xffe00000) != 0xffe00000)
|
|
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 */
|