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/*
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* DCA compatible decoder
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* Copyright (C) 2004 Gildas Bazin
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* Copyright (C) 2004 Benjamin Zores
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* Copyright (C) 2006 Benjamin Larsson
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* Copyright (C) 2007 Konstantin Shishkov
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef AVCODEC_DCA_H
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#define AVCODEC_DCA_H
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#include <stdint.h>
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#include "libavutil/float_dsp.h"
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Add support for building shared libraries with MSVC
This requires the makedef perl script by Derek, from the
c89-to-c99 repo. That scripts produces a .def file, listing
the symbols to be exported, based on the gcc version scripts
and the built object files.
To properly load non-function symbols from DLL files, the
data symbol declarations need to have the attribute
__declspec(dllimport) when building the calling code. (On mingw,
the linker can fix this up automatically, which is why it has not
been an issue so far. If this attribute is omitted, linking
actually succeeds, but reads from the table will not produce the
desired results at runtime.)
MSVC seems to manage to link DLLs (and run properly) even if
this attribute is present while building the library itself
(which normally isn't recommended) - other object files in the
same library manage to link to the symbol (with a small warning
at link time, like "warning LNK4049: locally defined symbol
_avpriv_mpa_bitrate_tab imported" - it doesn't seem to be possible
to squelch this warning), and the definition of the tables
themselves produce a warning that can be squelched ("warning C4273:
'avpriv_mpa_bitrate_tab' : inconsistent dll linkage, see previous
definition of 'avpriv_mpa_bitrate_tab').
In this setup, mingw isn't able to link object files that refer to
data symbols with __declspec(dllimport) without those symbols
actually being linked via a DLL (linking avcodec.dll ends up with
errors like "undefined reference to `__imp__avpriv_mpa_freq_tab'").
The dllimport declspec isn't needed at all in mingw, so we simply
choose not to declare it for other compilers than MSVC that requires
it. (If ICL support later requires it, the condition can be extended
later to include both of them.)
This also implies that code that is built to link to a certain
library as a DLL can't link to the same library as a static library.
Therefore, we only allow building either static or shared but not
both at the same time. (That is, static libraries as such can be,
and actually are, built - this is used for linking the test tools to
internal symbols in the libraries - but e.g. libavformat built to
link to libavcodec as a DLL cannot link statically to libavcodec.)
Also, linking to DLLs is slightly different from linking to shared
libraries on other platforms. DLLs use a thing called import
libraries, which is basically a stub library allowing the linker
to know which symbols exist in the DLL and what name the DLL will
have at runtime.
In mingw/gcc, the import library is usually named libfoo.dll.a,
which goes next to a static library named libfoo.a. This allows
gcc to pick the dynamic one, if available, from the normal -lfoo
switches, just as it does for libfoo.a vs libfoo.so on Unix. On
MSVC however, you need to literally specify the name of the import
library instead of the static library.
Signed-off-by: Martin Storsjö <martin@martin.st>
12 years ago
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#include "libavutil/internal.h"
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#include "avcodec.h"
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#include "dcadsp.h"
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#include "fmtconvert.h"
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#include "get_bits.h"
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#define DCA_PRIM_CHANNELS_MAX (7)
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#define DCA_ABITS_MAX (32) /* Should be 28 */
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#define DCA_SUBSUBFRAMES_MAX (4)
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#define DCA_SUBFRAMES_MAX (16)
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#define DCA_BLOCKS_MAX (16)
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#define DCA_LFE_MAX (3)
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#define DCA_CHSETS_MAX (4)
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#define DCA_CHSET_CHANS_MAX (8)
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#define DCA_PRIM_CHANNELS_MAX (7)
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#define DCA_ABITS_MAX (32) /* Should be 28 */
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#define DCA_SUBSUBFRAMES_MAX (4)
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#define DCA_SUBFRAMES_MAX (16)
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#define DCA_BLOCKS_MAX (16)
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#define DCA_LFE_MAX (3)
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#define DCA_XLL_FBANDS_MAX (4)
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#define DCA_XLL_SEGMENTS_MAX (16)
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#define DCA_XLL_CHSETS_MAX (16)
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#define DCA_XLL_CHANNELS_MAX (16)
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#define DCA_XLL_AORDER_MAX (15)
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/* Arbitrary limit; not sure what the maximum really is, but much larger. */
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#define DCA_XLL_DMIX_NCOEFFS_MAX (18)
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#define DCA_MAX_FRAME_SIZE 16384
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#define DCA_MAX_EXSS_HEADER_SIZE 4096
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#define DCA_BUFFER_PADDING_SIZE 1024
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enum DCAExtensionMask {
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DCA_EXT_CORE = 0x001, ///< core in core substream
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DCA_EXT_XXCH = 0x002, ///< XXCh channels extension in core substream
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DCA_EXT_X96 = 0x004, ///< 96/24 extension in core substream
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DCA_EXT_XCH = 0x008, ///< XCh channel extension in core substream
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DCA_EXT_EXSS_CORE = 0x010, ///< core in ExSS (extension substream)
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DCA_EXT_EXSS_XBR = 0x020, ///< extended bitrate extension in ExSS
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DCA_EXT_EXSS_XXCH = 0x040, ///< XXCh channels extension in ExSS
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DCA_EXT_EXSS_X96 = 0x080, ///< 96/24 extension in ExSS
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DCA_EXT_EXSS_LBR = 0x100, ///< low bitrate component in ExSS
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DCA_EXT_EXSS_XLL = 0x200, ///< lossless extension in ExSS
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};
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typedef struct XllChSetSubHeader {
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int channels; ///< number of channels in channel set, at most 16
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int residual_encode; ///< residual channel encoding
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int bit_resolution; ///< input sample bit-width
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int bit_width; ///< original input sample bit-width
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int sampling_frequency; ///< sampling frequency
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int samp_freq_interp; ///< sampling frequency interpolation multiplier
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int replacement_set; ///< replacement channel set group
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int active_replace_set; ///< current channel set is active channel set
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int primary_ch_set;
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int downmix_coeff_code_embedded;
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int downmix_embedded;
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int downmix_type;
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int hier_chset; ///< hierarchical channel set
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int downmix_ncoeffs;
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int downmix_coeffs[DCA_XLL_DMIX_NCOEFFS_MAX];
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int ch_mask_enabled;
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int ch_mask;
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int mapping_coeffs_present;
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int num_freq_bands;
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/* m_nOrigChanOrder */
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uint8_t orig_chan_order[DCA_XLL_FBANDS_MAX][DCA_XLL_CHANNELS_MAX];
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uint8_t orig_chan_order_inv[DCA_XLL_FBANDS_MAX][DCA_XLL_CHANNELS_MAX];
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/* Coefficients for channel pairs (at most 8), m_anPWChPairsCoeffs */
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int8_t pw_ch_pairs_coeffs[DCA_XLL_FBANDS_MAX][DCA_XLL_CHANNELS_MAX/2];
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/* m_nCurrHighestLPCOrder */
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uint8_t adapt_order_max[DCA_XLL_FBANDS_MAX];
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/* m_pnAdaptPredOrder */
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uint8_t adapt_order[DCA_XLL_FBANDS_MAX][DCA_XLL_CHANNELS_MAX];
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/* m_pnFixedPredOrder */
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uint8_t fixed_order[DCA_XLL_FBANDS_MAX][DCA_XLL_CHANNELS_MAX];
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/* m_pnLPCReflCoeffsQInd, unsigned version */
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uint8_t lpc_refl_coeffs_q_ind[DCA_XLL_FBANDS_MAX]
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[DCA_XLL_CHANNELS_MAX][DCA_XLL_AORDER_MAX];
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int lsb_fsize[DCA_XLL_FBANDS_MAX];
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int8_t scalable_lsbs[DCA_XLL_FBANDS_MAX][DCA_XLL_CHANNELS_MAX];
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int8_t bit_width_adj_per_ch[DCA_XLL_FBANDS_MAX][DCA_XLL_CHANNELS_MAX];
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} XllChSetSubHeader;
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typedef struct XllNavi {
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GetBitContext gb; // Context for parsing the data segments
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unsigned band_size[DCA_XLL_FBANDS_MAX];
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unsigned segment_size[DCA_XLL_FBANDS_MAX][DCA_XLL_SEGMENTS_MAX];
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unsigned chset_size[DCA_XLL_FBANDS_MAX][DCA_XLL_SEGMENTS_MAX][DCA_XLL_CHSETS_MAX];
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} XllNavi;
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typedef struct QMF64_table {
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float dct4_coeff[32][32];
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float dct2_coeff[32][32];
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float rcos[32];
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float rsin[32];
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} QMF64_table;
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/* Primary audio coding header */
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typedef struct DCAAudioHeader {
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int subband_activity[DCA_PRIM_CHANNELS_MAX]; ///< subband activity count
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int vq_start_subband[DCA_PRIM_CHANNELS_MAX]; ///< high frequency vq start subband
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int joint_intensity[DCA_PRIM_CHANNELS_MAX]; ///< joint intensity coding index
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int transient_huffman[DCA_PRIM_CHANNELS_MAX]; ///< transient mode code book
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int scalefactor_huffman[DCA_PRIM_CHANNELS_MAX]; ///< scale factor code book
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int bitalloc_huffman[DCA_PRIM_CHANNELS_MAX]; ///< bit allocation quantizer select
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int quant_index_huffman[DCA_PRIM_CHANNELS_MAX][DCA_ABITS_MAX]; ///< quantization index codebook select
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float scalefactor_adj[DCA_PRIM_CHANNELS_MAX][DCA_ABITS_MAX]; ///< scale factor adjustment
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int subframes; ///< number of subframes
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int total_channels; ///< number of channels including extensions
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int prim_channels; ///< number of primary audio channels
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} DCAAudioHeader;
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typedef struct DCAChan {
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DECLARE_ALIGNED(32, float, subband_samples)[DCA_BLOCKS_MAX][DCA_SUBBANDS][8];
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/* Subband samples history (for ADPCM) */
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DECLARE_ALIGNED(16, float, subband_samples_hist)[DCA_SUBBANDS][4];
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int hist_index;
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/* Half size is sufficient for core decoding, but for 96 kHz data
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* we need QMF with 64 subbands and 1024 samples. */
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DECLARE_ALIGNED(32, float, subband_fir_hist)[1024];
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DECLARE_ALIGNED(32, float, subband_fir_noidea)[64];
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/* Primary audio coding side information */
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int prediction_mode[DCA_SUBBANDS]; ///< prediction mode (ADPCM used or not)
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int prediction_vq[DCA_SUBBANDS]; ///< prediction VQ coefs
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int bitalloc[DCA_SUBBANDS]; ///< bit allocation index
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int transition_mode[DCA_SUBBANDS]; ///< transition mode (transients)
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int32_t scale_factor[DCA_SUBBANDS][2];///< scale factors (2 if transient)
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int joint_huff; ///< joint subband scale factors codebook
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int joint_scale_factor[DCA_SUBBANDS]; ///< joint subband scale factors
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int32_t high_freq_vq[DCA_SUBBANDS]; ///< VQ encoded high frequency subbands
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} DCAChan;
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typedef struct DCAContext {
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const AVClass *class; ///< class for AVOptions
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AVCodecContext *avctx;
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/* Frame header */
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int frame_type; ///< type of the current frame
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int samples_deficit; ///< deficit sample count
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int crc_present; ///< crc is present in the bitstream
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int sample_blocks; ///< number of PCM sample blocks
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int frame_size; ///< primary frame byte size
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int amode; ///< audio channels arrangement
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int sample_rate; ///< audio sampling rate
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int bit_rate; ///< transmission bit rate
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int bit_rate_index; ///< transmission bit rate index
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int dynrange; ///< embedded dynamic range flag
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int timestamp; ///< embedded time stamp flag
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int aux_data; ///< auxiliary data flag
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int hdcd; ///< source material is mastered in HDCD
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int ext_descr; ///< extension audio descriptor flag
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int ext_coding; ///< extended coding flag
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int aspf; ///< audio sync word insertion flag
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int lfe; ///< low frequency effects flag
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int predictor_history; ///< predictor history flag
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int header_crc; ///< header crc check bytes
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int multirate_inter; ///< multirate interpolator switch
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int version; ///< encoder software revision
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int copy_history; ///< copy history
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int source_pcm_res; ///< source pcm resolution
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int front_sum; ///< front sum/difference flag
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int surround_sum; ///< surround sum/difference flag
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int dialog_norm; ///< dialog normalisation parameter
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/* Primary audio coding header */
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DCAAudioHeader audio_header;
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/* Primary audio coding side information */
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int subsubframes[DCA_SUBFRAMES_MAX]; ///< number of subsubframes
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int partial_samples[DCA_SUBFRAMES_MAX]; ///< partial subsubframe samples count
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float downmix_coef[DCA_PRIM_CHANNELS_MAX + 1][2]; ///< stereo downmix coefficients
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int dynrange_coef; ///< dynamic range coefficient
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/* Core substream's embedded downmix coefficients (cf. ETSI TS 102 114 V1.4.1)
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* Input: primary audio channels (incl. LFE if present)
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* Output: downmix audio channels (up to 4, no LFE) */
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uint8_t core_downmix; ///< embedded downmix coefficients available
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uint8_t core_downmix_amode; ///< audio channel arrangement of embedded downmix
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uint16_t core_downmix_codes[DCA_PRIM_CHANNELS_MAX + 1][4]; ///< embedded downmix coefficients (9-bit codes)
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float lfe_data[2 * DCA_LFE_MAX * (DCA_BLOCKS_MAX + 4)]; ///< Low frequency effect data
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int lfe_scale_factor;
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/* Subband samples history (for ADPCM) */
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DECLARE_ALIGNED(32, float, raXin)[32];
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DCAChan dca_chan[DCA_PRIM_CHANNELS_MAX];
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int output; ///< type of output
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float *samples_chanptr[DCA_PRIM_CHANNELS_MAX + 1];
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float *extra_channels[DCA_PRIM_CHANNELS_MAX + 1];
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uint8_t *extra_channels_buffer;
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unsigned int extra_channels_buffer_size;
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uint8_t dca_buffer[DCA_MAX_FRAME_SIZE + DCA_MAX_EXSS_HEADER_SIZE + DCA_BUFFER_PADDING_SIZE];
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int dca_buffer_size; ///< how much data is in the dca_buffer
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const int8_t *channel_order_tab; ///< channel reordering table, lfe and non lfe
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GetBitContext gb;
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/* Current position in DCA frame */
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int current_subframe;
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int current_subsubframe;
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int core_ext_mask; ///< present extensions in the core substream
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int exss_ext_mask; ///< Non-core extensions
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/* XCh extension information */
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int xch_present; ///< XCh extension present and valid
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int xch_base_channel; ///< index of first (only) channel containing XCH data
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int xch_disable; ///< whether the XCh extension should be decoded or not
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/* XXCH extension information */
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int xxch_chset;
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int xxch_nbits_spk_mask;
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uint32_t xxch_core_spkmask;
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uint32_t xxch_spk_masks[4]; /* speaker masks, last element is core mask */
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int xxch_chset_nch[4];
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float xxch_dmix_sf[DCA_CHSETS_MAX];
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uint32_t xxch_dmix_embedded; /* lower layer has mix pre-embedded, per chset */
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float xxch_dmix_coeff[DCA_PRIM_CHANNELS_MAX][32]; /* worst case sizing */
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int8_t xxch_order_tab[32];
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int8_t lfe_index;
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/* XLL extension information */
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int xll_disable;
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int xll_nch_sets; ///< number of channel sets per frame
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int xll_channels; ///< total number of channels (in all channel sets)
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int xll_residual_channels; ///< number of residual channels
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int xll_segments; ///< number of segments per frame
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int xll_log_smpl_in_seg; ///< supposedly this is "nBits4SamplLoci"
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int xll_smpl_in_seg; ///< samples in segment per one frequency band for the first channel set
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int xll_bits4seg_size; ///< number of bits used to read segment size
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int xll_banddata_crc; ///< presence of CRC16 within each frequency band
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int xll_scalable_lsb;
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int xll_bits4ch_mask; ///< channel position mask
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int xll_fixed_lsb_width;
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XllChSetSubHeader xll_chsets[DCA_XLL_CHSETS_MAX];
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XllNavi xll_navi;
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int *xll_sample_buf;
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unsigned int xll_sample_buf_size;
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/* ExSS header parser */
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int static_fields; ///< static fields present
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int mix_metadata; ///< mixing metadata present
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int num_mix_configs; ///< number of mix out configurations
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int mix_config_num_ch[4]; ///< number of channels in each mix out configuration
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int profile;
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int one2one_map_chtospkr;
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int debug_flag; ///< used for suppressing repeated error messages output
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AVFloatDSPContext *fdsp;
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FFTContext imdct;
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SynthFilterContext synth;
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DCADSPContext dcadsp;
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QMF64_table *qmf64_table;
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FmtConvertContext fmt_conv;
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} DCAContext;
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Add support for building shared libraries with MSVC
This requires the makedef perl script by Derek, from the
c89-to-c99 repo. That scripts produces a .def file, listing
the symbols to be exported, based on the gcc version scripts
and the built object files.
To properly load non-function symbols from DLL files, the
data symbol declarations need to have the attribute
__declspec(dllimport) when building the calling code. (On mingw,
the linker can fix this up automatically, which is why it has not
been an issue so far. If this attribute is omitted, linking
actually succeeds, but reads from the table will not produce the
desired results at runtime.)
MSVC seems to manage to link DLLs (and run properly) even if
this attribute is present while building the library itself
(which normally isn't recommended) - other object files in the
same library manage to link to the symbol (with a small warning
at link time, like "warning LNK4049: locally defined symbol
_avpriv_mpa_bitrate_tab imported" - it doesn't seem to be possible
to squelch this warning), and the definition of the tables
themselves produce a warning that can be squelched ("warning C4273:
'avpriv_mpa_bitrate_tab' : inconsistent dll linkage, see previous
definition of 'avpriv_mpa_bitrate_tab').
In this setup, mingw isn't able to link object files that refer to
data symbols with __declspec(dllimport) without those symbols
actually being linked via a DLL (linking avcodec.dll ends up with
errors like "undefined reference to `__imp__avpriv_mpa_freq_tab'").
The dllimport declspec isn't needed at all in mingw, so we simply
choose not to declare it for other compilers than MSVC that requires
it. (If ICL support later requires it, the condition can be extended
later to include both of them.)
This also implies that code that is built to link to a certain
library as a DLL can't link to the same library as a static library.
Therefore, we only allow building either static or shared but not
both at the same time. (That is, static libraries as such can be,
and actually are, built - this is used for linking the test tools to
internal symbols in the libraries - but e.g. libavformat built to
link to libavcodec as a DLL cannot link statically to libavcodec.)
Also, linking to DLLs is slightly different from linking to shared
libraries on other platforms. DLLs use a thing called import
libraries, which is basically a stub library allowing the linker
to know which symbols exist in the DLL and what name the DLL will
have at runtime.
In mingw/gcc, the import library is usually named libfoo.dll.a,
which goes next to a static library named libfoo.a. This allows
gcc to pick the dynamic one, if available, from the normal -lfoo
switches, just as it does for libfoo.a vs libfoo.so on Unix. On
MSVC however, you need to literally specify the name of the import
library instead of the static library.
Signed-off-by: Martin Storsjö <martin@martin.st>
12 years ago
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extern av_export const uint32_t avpriv_dca_sample_rates[16];
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/**
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* Convert bitstream to one representation based on sync marker
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*/
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int avpriv_dca_convert_bitstream(const uint8_t *src, int src_size, uint8_t *dst,
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int max_size);
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int ff_dca_xbr_parse_frame(DCAContext *s);
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int ff_dca_xxch_decode_frame(DCAContext *s);
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void ff_dca_exss_parse_header(DCAContext *s);
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int ff_dca_xll_decode_header(DCAContext *s);
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int ff_dca_xll_decode_navi(DCAContext *s, int asset_end);
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int ff_dca_xll_decode_audio(DCAContext *s, AVFrame *frame);
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#endif /* AVCODEC_DCA_H */
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