Allow hardcoding of ulaw and alaw tables.

Originally committed as revision 22762 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 3 insertions, 76 deletions

diff --git a/libavcodec/pcm.c b/libavcodec/pcm.c
index 1298121fac..b68da7c354 100644
--- a/libavcodec/pcm.c
+++ b/libavcodec/pcm.c
@@ -27,92 +27,19 @@
 #include "avcodec.h"
 #include "libavutil/common.h" /* for av_reverse */
 #include "bytestream.h"
+#include "pcm_tablegen.h"
 
 #define MAX_CHANNELS 64
 
-/* from g711.c by SUN microsystems (unrestricted use) */
-
-#define         SIGN_BIT        (0x80)      /* Sign bit for a A-law byte. */
-#define         QUANT_MASK      (0xf)       /* Quantization field mask. */
-#define         NSEGS           (8)         /* Number of A-law segments. */
-#define         SEG_SHIFT       (4)         /* Left shift for segment number. */
-#define         SEG_MASK        (0x70)      /* Segment field mask. */
-
-#define         BIAS            (0x84)      /* Bias for linear code. */
-
-/*
- * alaw2linear() - Convert an A-law value to 16-bit linear PCM
- *
- */
-static av_cold int alaw2linear(unsigned char a_val)
-{
-        int t;
-        int seg;
-
-        a_val ^= 0x55;
-
-        t = a_val & QUANT_MASK;
-        seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT;
-        if(seg) t= (t + t + 1 + 32) << (seg + 2);
-        else    t= (t + t + 1     ) << 3;
-
-        return (a_val & SIGN_BIT) ? t : -t;
-}
-
-static av_cold int ulaw2linear(unsigned char u_val)
-{
-        int t;
-
-        /* Complement to obtain normal u-law value. */
-        u_val = ~u_val;
-
-        /*
-         * Extract and bias the quantization bits. Then
-         * shift up by the segment number and subtract out the bias.
-         */
-        t = ((u_val & QUANT_MASK) << 3) + BIAS;
-        t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT;
-
-        return (u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS);
-}
-
-/* 16384 entries per table */
-static uint8_t linear_to_alaw[16384];
-static uint8_t linear_to_ulaw[16384];
-
-static av_cold void build_xlaw_table(uint8_t *linear_to_xlaw,
-                             int (*xlaw2linear)(unsigned char),
-                             int mask)
-{
-    int i, j, v, v1, v2;
-
-    j = 0;
-    for(i=0;i<128;i++) {
-        if (i != 127) {
-            v1 = xlaw2linear(i ^ mask);
-            v2 = xlaw2linear((i + 1) ^ mask);
-            v = (v1 + v2 + 4) >> 3;
-        } else {
-            v = 8192;
-        }
-        for(;j<v;j++) {
-            linear_to_xlaw[8192 + j] = (i ^ mask);
-            if (j > 0)
-                linear_to_xlaw[8192 - j] = (i ^ (mask ^ 0x80));
-        }
-    }
-    linear_to_xlaw[0] = linear_to_xlaw[1];
-}
-
 static av_cold int pcm_encode_init(AVCodecContext *avctx)
 {
     avctx->frame_size = 1;
     switch(avctx->codec->id) {
     case CODEC_ID_PCM_ALAW:
-        build_xlaw_table(linear_to_alaw, alaw2linear, 0xd5);
+        pcm_alaw_tableinit();
         break;
     case CODEC_ID_PCM_MULAW:
-        build_xlaw_table(linear_to_ulaw, ulaw2linear, 0xff);
+        pcm_ulaw_tableinit();
         break;
     default:
         break;