[bTSstream-devel] Incomplete ATSC A/52 support

Benjamin Cohen git at videolan.org
Thu Dec 19 01:08:59 CET 2013


bitstream | branch: master | Benjamin Cohen <bencoh at notk.org> | Tue Dec 17 16:42:46 2013 +0100| [0be9f7f883018fde7d8e955078ee61f8dbd6072e] | committer: Benjamin Cohen

Incomplete ATSC A/52 support

> http://git.videolan.org/gitweb.cgi/bitstream.git/?a=commit;h=0be9f7f883018fde7d8e955078ee61f8dbd6072e
---

 atsc/a52.h |  284 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 284 insertions(+)

diff --git a/atsc/a52.h b/atsc/a52.h
new file mode 100644
index 0000000..17d78d8
--- /dev/null
+++ b/atsc/a52.h
@@ -0,0 +1,284 @@
+/*****************************************************************************
+ * a52.h: ATSC A/52:2012 Digital Audio Compression Standard
+ *****************************************************************************
+ * Copyright (C) 2013 VideoLAN
+ *
+ * Authors: Benjamin Cohen <bencoh at notk.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject
+ * to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *****************************************************************************/
+
+/*
+ * Normative references:
+ * - ATSC A/52:2012
+ */
+
+#ifndef __BITSTREAM_ATSC_A52_H__
+#define __BITSTREAM_ATSC_A52_H__
+
+#include <stdint.h>   /* uint8_t, uint16_t, etc... */
+#include <stdbool.h>  /* bool */
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+#define A52_BSID                8
+#define A52_BSID_ANNEX_D        1
+#define A52_BSID_ANNEX_E        16
+
+#define A52_FSCOD_48KHZ         0
+#define A52_FSCOD_441KHZ        1
+#define A52_FSCOD_32KHZ         2
+#define A52_FSCOD_RESERVED      3
+
+/*****************************************************************************
+ * A/52 syncinfo (A/52:2012 Table 5.1)
+ * - syncword       16
+ * - crc1           16
+ * - fscod          2
+ * - frmsizecod     6
+ *****************************************************************************/
+
+/* A/52 Frame Size Code Table (A/52:2012 Table 5.18) */
+static const uint16_t a52_frame_size_code_tab[38][3] = {
+    { 64,   69,   96   },
+    { 64,   70,   96   },
+    { 80,   87,   120  },
+    { 80,   88,   120  },
+    { 96,   104,  144  },
+    { 96,   105,  144  },
+    { 112,  121,  168  },
+    { 112,  122,  168  },
+    { 128,  139,  192  },
+    { 128,  140,  192  },
+    { 160,  174,  240  },
+    { 160,  175,  240  },
+    { 192,  208,  288  },
+    { 192,  209,  288  },
+    { 224,  243,  336  },
+    { 224,  244,  336  },
+    { 256,  278,  384  },
+    { 256,  279,  384  },
+    { 320,  348,  480  },
+    { 320,  349,  480  },
+    { 384,  417,  576  },
+    { 384,  418,  576  },
+    { 448,  487,  672  },
+    { 448,  488,  672  },
+    { 512,  557,  768  },
+    { 512,  558,  768  },
+    { 640,  696,  960  },
+    { 640,  697,  960  },
+    { 768,  835,  1152 },
+    { 768,  836,  1152 },
+    { 896,  975,  1344 },   
+    { 896,  976,  1344 },
+    { 1024, 1114, 1536 },
+    { 1024, 1115, 1536 },
+    { 1152, 1253, 1728 },
+    { 1152, 1254, 1728 },
+    { 1280, 1393, 1920 },
+    { 1280, 1394, 1920 },
+};
+
+/* A/52 Bitrate Table (A/52:2012 Table 5.18) */
+static const uint16_t a52_bitrate_tab[38] = {
+    64, 64,
+    80, 80,
+    96, 96,
+    112, 112,
+    128, 128,
+    160, 160,
+    192, 192,
+    224, 224,
+    256, 256,
+    320, 320,
+    384, 384,
+    448, 448,
+    512, 512,
+    640, 640,
+    768, 768,
+    896, 896,
+    1024, 1024,
+    1152, 1152,
+    1280, 1280
+};
+
+static inline uint16_t a52_get_sync(const uint8_t *p_a52)
+{
+    return (p_a52[0] << 8 | p_a52[1]);
+}
+
+static inline void a52_set_sync(uint8_t *p_a52)
+{
+    p_a52[0] = 0xb;
+    p_a52[1] = 0x77;
+}
+
+static inline uint16_t a52_get_crc(const uint8_t *p_a52)
+{
+    return (p_a52[2] << 8 | p_a52[3]);
+}
+
+static inline void a52_set_crc(uint8_t *p_a52, uint16_t i_crc)
+{
+    p_a52[2] = i_crc >> 8;
+    p_a52[3] = i_crc & 0xff;
+}
+
+static inline uint8_t a52_get_fscod(const uint8_t *p_a52)
+{
+    return (p_a52[4] & 0xc0) >> 6;
+}
+
+static inline void a52_set_fscod(uint8_t *p_a52, uint8_t i_fscod)
+{
+    p_a52[4] &= ~0xc0;
+    p_a52[4] |= (i_fscod & 0x3) << 6;
+}
+
+static inline uint8_t a52_get_frmsizecod(const uint8_t *p_a52)
+{
+    return p_a52[4] & 0x3f;
+}
+
+static inline void a52_set_frmsizecod(uint8_t *p_a52, uint8_t i_frmsizecod)
+{
+    p_a52[4] &= ~0x3f;
+    p_a52[4] |= i_frmsizecod & 0x3f;
+}
+
+static inline uint16_t a52_get_frame_size(uint8_t i_fscod, uint8_t i_frmsizecod)
+{
+    i_fscod &= 0x3;
+    if ((i_fscod == A52_FSCOD_RESERVED) || (i_frmsizecod > 37)) {
+        return 0;
+    }
+    return a52_frame_size_code_tab[i_frmsizecod][i_fscod] * 2;
+}
+
+/*****************************************************************************
+ * A/52 bsi (Bit Stream Information)
+ *****************************************************************************/
+
+static inline uint8_t a52_get_bsid(const uint8_t *p_a52)
+{
+    return (p_a52[5] & 0xf8) >> 3;
+}
+
+static inline void a52_set_bsid(uint8_t *p_a52, uint8_t i_bsid)
+{
+    p_a52[5] &= ~0xf8;
+    p_a52[5] |= (i_bsid & 0xf8) << 3;
+}
+
+static inline uint8_t a52_get_bsmod(const uint8_t *p_a52)
+{
+    return (p_a52[5] & 0x7);
+}
+
+static inline void a52_set_bsmod(uint8_t *p_a52, uint8_t i_bsid)
+{
+    p_a52[5] &= ~0x7;
+    p_a52[5] |= i_bsid & 0x7;
+}
+
+static inline uint8_t a52_get_acmod(const uint8_t *p_a52)
+{
+    return (p_a52[6] & 0xe0) >> 5;
+}
+
+static inline void a52_set_acmod(uint8_t *p_a52, uint8_t i_acmod)
+{
+    p_a52[6] &= ~0xe0;
+    p_a52[6] |= (i_acmod & 0x7) << 5;
+}
+
+static inline uint8_t a52_get_cmixlev(const uint8_t *p_a52)
+{
+    return (p_a52[6] & 0x18) >> 3;
+}
+
+static inline void a52_set_cmixlev(uint8_t *p_a52, uint8_t i_cmixlev)
+{
+    p_a52[6] &= ~0x18;
+    p_a52[6] |= (i_cmixlev & 0x3) << 3;
+}
+
+/*****************************************************************************
+ * A/52 Annex E 
+ *****************************************************************************/
+static inline uint8_t a52e_get_strmtyp(const uint8_t *p_a52)
+{
+    return (p_a52[2] & 0xc0) >> 5;
+}
+
+static inline void a52e_set_strmtyp(uint8_t *p_a52, uint8_t i_strmtyp)
+{
+    p_a52[2] &= ~0xc0;
+    p_a52[2] |= (i_strmtyp & 0x3) << 6;
+}
+
+static inline uint8_t a52e_get_substreamid(const uint8_t *p_a52)
+{
+    return (p_a52[2] & 0x38) >> 3;
+}
+
+static inline void a52e_set_substreamid(uint8_t *p_a52, uint8_t i_substreamid)
+{
+    p_a52[2] &= ~0x38;
+    p_a52[2] |= (i_substreamid & 0x7) << 3;
+}
+
+static inline uint16_t a52e_get_frmsiz(const uint8_t *p_a52)
+{
+    return ((p_a52[2] & 0x7) << 8) | p_a52[3];
+}
+
+static inline void a52e_set_frmsiz(uint8_t *p_a52, uint16_t i_frmsiz)
+{
+    p_a52[2] &= ~0x7;
+    p_a52[2] |= (i_frmsiz >> 8) & 0x7;
+    p_a52[3] |= i_frmsiz & 0xff;
+}
+
+static inline uint16_t a52e_get_frame_size(uint16_t i_frmsiz)
+{
+    return (i_frmsiz + 1) * 2;
+}
+
+static inline uint8_t a52e_get_fscod(const uint8_t *p_a52)
+{
+    return (p_a52[4] & 0xc0) >> 6;
+}
+
+static inline void a52e_set_fscod(uint8_t *p_a52, uint8_t i_fscod)
+{
+    p_a52[4] &= ~0xc0;
+    p_a52[4] |= (i_fscod & 0x3) << 6;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif



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