mmaldec: limit internal buffering

[ffmpeg] / libavcodec / atrac.h

diff --git a/libavcodec/atrac.h b/libavcodec/atrac.h
index 7175700d3c971bf0fb01defdf4ff95258d3423c9..8909323b013a6bf8fe2a6b11b1bb35020b9984b8 100644 (file)
--- a/libavcodec/atrac.h
+++ b/libavcodec/atrac.h
@@ -1,38 +1,96 @@
 /*
- * Atrac common data
- * Copyright (c) 2009 Maxim Poliakovski
+ * common functions for the ATRAC family of decoders
+ *
+ * Copyright (c) 2009-2013 Maxim Poliakovski
  * Copyright (c) 2009 Benjamin Larsson
  *
- * 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
  */
 
 /**
- * @file libavcodec/atrac1data.h
- * Atrac 1 compatible decoder data
+ * @file
+ * ATRAC common header
  */
 
 #ifndef AVCODEC_ATRAC_H
 #define AVCODEC_ATRAC_H
 
+/**
+ *  Gain control parameters for one subband.
+ */
+typedef struct AtracGainInfo {
+    int   num_points;   ///< number of gain control points
+    int   lev_code[7];  ///< level at corresponding control point
+    int   loc_code[7];  ///< location of gain control points
+} AtracGainInfo;
+
+/**
+ *  Gain compensation context structure.
+ */
+typedef struct AtracGCContext {
+    float   gain_tab1[16];  ///< gain compensation level table
+    float   gain_tab2[31];  ///< gain compensation interpolation table
+    int     id2exp_offset;  ///< offset for converting level index into level exponent
+    int     loc_scale;      ///< scale of location code = 2^loc_scale samples
+    int     loc_size;       ///< size of location code in samples
+} AtracGCContext;
+
+extern float ff_atrac_sf_table[64];
+
+/**
+ * Generate common tables.
+ */
+void ff_atrac_generate_tables(void);
+
+/**
+ *  Initialize gain compensation context.
+ *
+ * @param gctx            pointer to gain compensation context to initialize
+ * @param id2exp_offset   offset for converting level index into level exponent
+ * @param loc_scale       location size factor
+ */
+void ff_atrac_init_gain_compensation(AtracGCContext *gctx, int id2exp_offset,
+                                     int loc_scale);
 
-extern float sf_table[64];
-extern float qmf_window[48];
+/**
+ * Apply gain compensation and perform the MDCT overlapping part.
+ *
+ * @param gctx         pointer to gain compensation context
+ * @param in           input buffer
+ * @param prev         previous buffer to perform overlap against
+ * @param gc_now       gain control information for current frame
+ * @param gc_next      gain control information for next frame
+ * @param num_samples  number of samples to process
+ * @param out          output data goes here
+ */
+void ff_atrac_gain_compensation(AtracGCContext *gctx, float *in, float *prev,
+                                AtracGainInfo *gc_now, AtracGainInfo *gc_next,
+                                int num_samples, float *out);
 
-void atrac_generate_tables(void);
-void atrac_iqmf (float *inlo, float *inhi, unsigned int nIn, float *pOut, float *delayBuf, float *temp);
+/**
+ * Quadrature mirror synthesis filter.
+ *
+ * @param inlo      lower part of spectrum
+ * @param inhi      higher part of spectrum
+ * @param nIn       size of spectrum buffer
+ * @param pOut      out buffer
+ * @param delayBuf  delayBuf buffer
+ * @param temp      temp buffer
+ */
+void ff_atrac_iqmf (float *inlo, float *inhi, unsigned int nIn, float *pOut, float *delayBuf, float *temp);
 
 #endif /* AVCODEC_ATRAC_H */