minor simplifications in cabac_mb_type

[ffmpeg] / libavcodec / mpegaudio.h

diff --git a/libavcodec/mpegaudio.h b/libavcodec/mpegaudio.h
index 7dc206a1e64b2b198714cbb26f431c8c9966018c..0ee58240c237d0cb48f567fdac4a37936faa0f86 100644 (file)
--- a/libavcodec/mpegaudio.h
+++ b/libavcodec/mpegaudio.h
@@ -1,7 +1,10 @@
-/* mpeg audio declarations for both encoder and decoder */
+/**
+ * @file mpegaudio.h
+ * mpeg audio declarations for both encoder and decoder.
+ */
 
 /* max frame size, in samples */
-#define MPA_FRAME_SIZE 1152 
+#define MPA_FRAME_SIZE 1152
 
 /* max compressed frame size */
 #define MPA_MAX_CODED_FRAME_SIZE 1792
@@ -15,13 +18,69 @@
 #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]);
 
-const UINT16 mpa_bitrate_tab[2][3][15];
-const UINT16 mpa_freq_tab[3];
+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 mpa_enwindow[257];
+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;
+}