X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fmlp.h;h=d7711126b8aaac5d5a6cf80702f12734dad263e5;hb=f07ef2d9c9e9d1e84c532e9102594834e88a5c83;hp=43c3b272a5225d4721fe0609c6a667b8802c0293;hpb=ce15710f554ef3520f968c8b4284a0f576611c95;p=ffmpeg diff --git a/libavcodec/mlp.h b/libavcodec/mlp.h index 43c3b272a52..d7711126b8a 100644 --- a/libavcodec/mlp.h +++ b/libavcodec/mlp.h @@ -2,74 +2,86 @@ * MLP codec common header file * Copyright (c) 2007-2008 Ian Caulfield * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav 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, + * Libav 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 + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ -#ifndef FFMPEG_MLP_H -#define FFMPEG_MLP_H +#ifndef AVCODEC_MLP_H +#define AVCODEC_MLP_H #include #include "avcodec.h" -/** Maximum number of channels that can be decoded. */ -#define MAX_CHANNELS 16 +/** Last possible matrix channel for each codec */ +#define MAX_MATRIX_CHANNEL_MLP 5 +#define MAX_MATRIX_CHANNEL_TRUEHD 7 +/** Maximum number of channels in a valid stream. + * MLP : 5.1 + 2 noise channels -> 8 channels + * TrueHD: 7.1 -> 8 channels + */ +#define MAX_CHANNELS 8 /** Maximum number of matrices used in decoding; most streams have one matrix * per output channel, but some rematrix a channel (usually 0) more than once. */ +#define MAX_MATRICES_MLP 6 +#define MAX_MATRICES_TRUEHD 8 +#define MAX_MATRICES 8 -#define MAX_MATRICES 15 - -/** Maximum number of substreams that can be decoded. This could also be set - * higher, but I haven't seen any examples with more than two. */ -#define MAX_SUBSTREAMS 2 +/** Maximum number of substreams that can be decoded. + * MLP's limit is 2. TrueHD supports at least up to 3. + */ +#define MAX_SUBSTREAMS 3 +/** which multiple of 48000 the maximum sample rate is */ +#define MAX_RATEFACTOR 4 /** maximum sample frequency seen in files */ -#define MAX_SAMPLERATE 192000 +#define MAX_SAMPLERATE (MAX_RATEFACTOR * 48000) /** maximum number of audio samples within one access unit */ -#define MAX_BLOCKSIZE (40 * (MAX_SAMPLERATE / 48000)) +#define MAX_BLOCKSIZE (40 * MAX_RATEFACTOR) /** next power of two greater than MAX_BLOCKSIZE */ -#define MAX_BLOCKSIZE_POW2 (64 * (MAX_SAMPLERATE / 48000)) +#define MAX_BLOCKSIZE_POW2 (64 * MAX_RATEFACTOR) /** number of allowed filters */ #define NUM_FILTERS 2 -/** The maximum number of taps in either the IIR or FIR filter; - * I believe MLP actually specifies the maximum order for IIR filters as four, - * and that the sum of the orders of both filters must be <= 8. */ -#define MAX_FILTER_ORDER 8 +/** The maximum number of taps in IIR and FIR filters. */ +#define MAX_FIR_ORDER 8 +#define MAX_IIR_ORDER 4 + +/** Code that signals end of a stream. */ +#define END_OF_STREAM 0xd234d234 #define FIR 0 #define IIR 1 /** filter data */ -typedef struct { +typedef struct FilterParams { uint8_t order; ///< number of taps in filter uint8_t shift; ///< Right shift to apply to output of filter. - int32_t coeff[MAX_FILTER_ORDER]; - int32_t state[MAX_FILTER_ORDER]; + int32_t state[MAX_FIR_ORDER]; } FilterParams; /** sample data coding information */ -typedef struct { +typedef struct ChannelParams { FilterParams filter_params[NUM_FILTERS]; + int32_t coeff[NUM_FILTERS][MAX_FIR_ORDER]; int16_t huff_offset; ///< Offset to apply to residual values. int32_t sign_huff_offset; ///< sign/rounding-corrected version of huff_offset @@ -80,30 +92,36 @@ typedef struct { /** Tables defining the Huffman codes. * There are three entropy coding methods used in MLP (four if you count * "none" as a method). These use the same sequences for codes starting with - * 00 or 01, but have different codes starting with 1. */ - + * 00 or 01, but have different codes starting with 1. + */ extern const uint8_t ff_mlp_huffman_tables[3][18][2]; /** MLP uses checksums that seem to be based on the standard CRC algorithm, but * are not (in implementation terms, the table lookup and XOR are reversed). * We can implement this behavior using a standard av_crc on all but the - * last element, then XOR that with the last element. */ - + * last element, then XOR that with the last element. + */ uint8_t ff_mlp_checksum8 (const uint8_t *buf, unsigned int buf_size); uint16_t ff_mlp_checksum16(const uint8_t *buf, unsigned int buf_size); /** Calculate an 8-bit checksum over a restart header -- a non-multiple-of-8 - * number of bits, starting two bits into the first byte of buf. */ - + * number of bits, starting two bits into the first byte of buf. + */ uint8_t ff_mlp_restart_checksum(const uint8_t *buf, unsigned int bit_size); /** XOR together all the bytes of a buffer. - * Does this belong in dspcontext? */ - + * Does this belong in dspcontext? + */ uint8_t ff_mlp_calculate_parity(const uint8_t *buf, unsigned int buf_size); -int ff_mlp_init_crc2D(AVCodecParserContext *s); +void ff_mlp_init_crc(void); -void ff_mlp_init_crc(); +/** XOR four bytes into one. */ +static inline uint8_t xor_32_to_8(uint32_t value) +{ + value ^= value >> 16; + value ^= value >> 8; + return value; +} -#endif /* FFMPEG_MLP_H */ +#endif /* AVCODEC_MLP_H */