minor simplifications in cabac_mb_type

[ffmpeg] / libavcodec / mpegaudio.h

diff --git a/libavcodec/mpegaudio.h b/libavcodec/mpegaudio.h
index 9d5fdfb0114823a11573a577771f6935ed2d97d0..0ee58240c237d0cb48f567fdac4a37936faa0f86 100644 (file)
--- a/libavcodec/mpegaudio.h
+++ b/libavcodec/mpegaudio.h
@@ -1,34 +1,86 @@
+/**
+ * @file mpegaudio.h
+ * mpeg audio declarations for both encoder and decoder.
+ */
+
+/* max frame size, in samples */
+#define MPA_FRAME_SIZE 1152
 
 /* max compressed frame size */
-#define MPA_MAX_CODED_FRAME_SIZE 1200
+#define MPA_MAX_CODED_FRAME_SIZE 1792
 
-#define MPA_FRAME_SIZE 1152 
 #define MPA_MAX_CHANNELS 2
 
-#define SAMPLES_BUF_SIZE 4096
 #define SBLIMIT 32 /* number of subbands */
-#define DCT_BITS 14 /* number of bits for the DCT */
-#define MUL(a,b) (((a) * (b)) >> DCT_BITS)
-#define FIX(a)   ((int)((a) * (1 << DCT_BITS)))
-
-typedef struct MpegAudioContext {
-    PutBitContext pb;
-    int nb_channels;
-    int freq, bit_rate;
-    int lsf;           /* 1 if mpeg2 low bitrate selected */
-    int bitrate_index; /* bit rate */
-    int freq_index;
-    int frame_size; /* frame size, in bits, without padding */
-    INT64 nb_samples; /* total number of samples encoded */
-    /* padding computation */
-    int frame_frac, frame_frac_incr, do_padding;
-    short samples_buf[MPA_MAX_CHANNELS][SAMPLES_BUF_SIZE]; /* buffer for filter */
-    int samples_offset[MPA_MAX_CHANNELS];       /* offset in samples_buf */
-    int sb_samples[MPA_MAX_CHANNELS][3][12][SBLIMIT];
-    unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3]; /* scale factors */
-    /* code to group 3 scale factors */
-    unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];       
-    int sblimit; /* number of used subbands */
-    const unsigned char *alloc_table;
-} MpegAudioContext;
 
+#define MPA_STEREO  0
+#define MPA_JSTEREO 1
+#define MPA_DUAL    2
+#define MPA_MONO    3
+
+/* header + layer + bitrate + freq + lsf/mpeg25 */
+#define SAME_HEADER_MASK \
+   (0xffe00000 | (3 << 17) | (0xf << 12) | (3 << 10) | (3 << 19))
+
+/* define USE_HIGHPRECISION to have a bit exact (but slower) mpeg
+   audio decoder */
+
+#ifdef USE_HIGHPRECISION
+#define FRAC_BITS   23   /* fractional bits for sb_samples and dct */
+#define WFRAC_BITS  16   /* fractional bits for window */
+#else
+#define FRAC_BITS   15   /* fractional bits for sb_samples and dct */
+#define WFRAC_BITS  14   /* fractional bits for window */
+#endif
+
+#if defined(USE_HIGHPRECISION) && defined(CONFIG_AUDIO_NONSHORT)
+typedef int32_t OUT_INT;
+#define OUT_MAX INT32_MAX
+#define OUT_MIN INT32_MIN
+#define OUT_SHIFT (WFRAC_BITS + FRAC_BITS - 31)
+#else
+typedef int16_t OUT_INT;
+#define OUT_MAX INT16_MAX
+#define OUT_MIN INT16_MIN
+#define OUT_SHIFT (WFRAC_BITS + FRAC_BITS - 15)
+#endif
+
+#if FRAC_BITS <= 15
+typedef int16_t MPA_INT;
+#else
+typedef int32_t MPA_INT;
+#endif
+
+int l2_select_table(int bitrate, int nb_channels, int freq, int lsf);
+int mpa_decode_header(AVCodecContext *avctx, uint32_t head);
+void ff_mpa_synth_init(MPA_INT *window);
+void ff_mpa_synth_filter(MPA_INT *synth_buf_ptr, int *synth_buf_offset,
+                         MPA_INT *window, int *dither_state,
+                         OUT_INT *samples, int incr,
+                         int32_t sb_samples[SBLIMIT]);
+
+extern const uint16_t mpa_bitrate_tab[2][3][15];
+extern const uint16_t mpa_freq_tab[3];
+extern const unsigned char *alloc_tables[5];
+extern const double enwindow[512];
+extern const int sblimit_table[5];
+extern const int quant_steps[17];
+extern const int quant_bits[17];
+extern const int32_t mpa_enwindow[257];
+
+/* 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;
+}