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-rw-r--r--libavcodec/Makefile1
-rw-r--r--libavcodec/pcm.c79
-rw-r--r--libavcodec/pcm_tablegen.c45
-rw-r--r--libavcodec/pcm_tablegen.h119
4 files changed, 168 insertions, 76 deletions
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 4667be2c8e..4fce1bb058 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -645,5 +645,6 @@ $(SUBDIR)dv.o: $(SUBDIR)dv_tables.h
$(SUBDIR)mdct.o: $(SUBDIR)mdct_tables.h
$(SUBDIR)mpegaudiodec.o: $(SUBDIR)mpegaudio_tables.h
$(SUBDIR)motionpixels.o: $(SUBDIR)motionpixels_tables.h
+$(SUBDIR)pcm.o: $(SUBDIR)pcm_tables.h
$(SUBDIR)qdm2.o: $(SUBDIR)qdm2_tables.h
endif
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;
diff --git a/libavcodec/pcm_tablegen.c b/libavcodec/pcm_tablegen.c
new file mode 100644
index 0000000000..57ecb43dc6
--- /dev/null
+++ b/libavcodec/pcm_tablegen.c
@@ -0,0 +1,45 @@
+/*
+ * Generate a header file for hardcoded PCM tables
+ *
+ * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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,
+ * 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
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdlib.h>
+#define CONFIG_HARDCODED_TABLES 0
+#include "pcm_tablegen.h"
+#include "tableprint.h"
+
+int main(void)
+{
+ pcm_alaw_tableinit();
+ pcm_ulaw_tableinit();
+
+ write_fileheader();
+
+ printf("static const uint8_t linear_to_alaw[1 << 14] = {\n");
+ write_uint8_array(linear_to_alaw, 1 << 14);
+ printf("};\n");
+
+ printf("static const uint8_t linear_to_ulaw[1 << 14] = {\n");
+ write_uint8_array(linear_to_ulaw, 1 << 14);
+ printf("};\n");
+
+ return 0;
+}
+
diff --git a/libavcodec/pcm_tablegen.h b/libavcodec/pcm_tablegen.h
new file mode 100644
index 0000000000..8921baaba2
--- /dev/null
+++ b/libavcodec/pcm_tablegen.h
@@ -0,0 +1,119 @@
+/*
+ * Header file for hardcoded PCM tables
+ *
+ * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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,
+ * 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
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef PCM_TABLEGEN_H
+#define PCM_TABLEGEN_H
+
+#include <stdint.h>
+#include "../libavutil/attributes.h"
+
+/* 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);
+}
+
+#if CONFIG_HARDCODED_TABLES
+#define pcm_alaw_tableinit()
+#define pcm_ulaw_tableinit()
+#include "libavcodec/pcm_tables.h"
+#else
+/* 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 void pcm_alaw_tableinit(void)
+{
+ build_xlaw_table(linear_to_alaw, alaw2linear, 0xd5);
+}
+
+static void pcm_ulaw_tableinit(void)
+{
+ build_xlaw_table(linear_to_ulaw, ulaw2linear, 0xff);
+}
+#endif /* CONFIG_HARDCODED_TABLES */
+
+#endif /* PCM_TABLEGEN_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-01 20:12:51 +0000