Add libcodec2 en/decoder

1 files changed, 82 insertions, 0 deletions

diff --git a/libavcodec/codec2utils.h b/libavcodec/codec2utils.h
new file mode 100644
index 0000000000..6def4d4aa3
--- /dev/null
+++ b/libavcodec/codec2utils.h
@@ -0,0 +1,82 @@
+/*
+ * codec2 utility functions
+ * Copyright (c) 2017 Tomas Härdin
+ *
+ * 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 AVCODEC_CODEC2UTILS_H
+#define AVCODEC_CODEC2UTILS_H
+
+#include <stdint.h>
+
+//Highest mode we're willing to use.
+//Don't want to let users accidentally produce files that can't be decoded in the future.
+//CODEC2_MODE_WB (9) is experimental/unstable as of 2017-11-23.
+#define AVPRIV_CODEC2_MODE_MAX 8 //CODEC2_MODE_700C
+
+//Used by both codec2raw demuxer and libcodec2 encoder.
+//The integers match the values in codec2.h, so "3200" -> CODEC2_MODE_3000 = 0 and so on.
+//It is possible that we're linked to a version of libcodec2 that lacks some of these modes.
+//For example Debian stretch ships with libcodec2.so.0.4 which lacks CODEC2_MODE_700C.
+#define AVPRIV_CODEC2_AVOPTIONS(desc, classname, min_val, default_val, option_flags) \
+    { "mode", desc, offsetof(classname, mode), AV_OPT_TYPE_INT, {.i64 = default_val}, min_val, AVPRIV_CODEC2_MODE_MAX, .flags=option_flags, .unit="codec2_mode"},\
+    { "3200", "3200", 0, AV_OPT_TYPE_CONST, {.i64 = 0}, .flags=option_flags, .unit="codec2_mode"},\
+    { "2400", "2400", 0, AV_OPT_TYPE_CONST, {.i64 = 1}, .flags=option_flags, .unit="codec2_mode"},\
+    { "1600", "1600", 0, AV_OPT_TYPE_CONST, {.i64 = 2}, .flags=option_flags, .unit="codec2_mode"},\
+    { "1400", "1400", 0, AV_OPT_TYPE_CONST, {.i64 = 3}, .flags=option_flags, .unit="codec2_mode"},\
+    { "1300", "1300", 0, AV_OPT_TYPE_CONST, {.i64 = 4}, .flags=option_flags, .unit="codec2_mode"},\
+    { "1200", "1200", 0, AV_OPT_TYPE_CONST, {.i64 = 5}, .flags=option_flags, .unit="codec2_mode"},\
+    { "700",  "700",  0, AV_OPT_TYPE_CONST, {.i64 = 6}, .flags=option_flags, .unit="codec2_mode"},\
+    { "700B", "700B", 0, AV_OPT_TYPE_CONST, {.i64 = 7}, .flags=option_flags, .unit="codec2_mode"},\
+    { "700C", "700C", 0, AV_OPT_TYPE_CONST, {.i64 = 8}, .flags=option_flags, .unit="codec2_mode"}
+
+//The three following functions are here to avoid needing libavformat/codec2.c to depend on libcodec2
+
+//Computes bitrate from mode, with frames rounded up to the nearest octet.
+//So 700 bit/s (28 bits/frame) becomes 800 bits/s (32 bits/frame).
+//logctx is used for av_log()
+//Returns <0 if mode is invalid
+int avpriv_codec2_mode_bit_rate(void *logctx, int mode);
+
+//Mimics codec2_samples_per_frame()
+int avpriv_codec2_mode_frame_size(void *logctx, int mode);
+
+//Mimics (codec2_bits_per_frame()+7)/8
+int avpriv_codec2_mode_block_align(void *logctx, int mode);
+
+#define AVPRIV_CODEC2_EXTRADATA_SIZE 4
+
+//Used in codec2raw demuxer and libcodec2 encoder
+static inline void avpriv_codec2_make_extradata(uint8_t *ptr, int mode) {
+    //version 0.8 as of 2017-12-23 (r3386)
+    ptr[0] = 0;     //major
+    ptr[1] = 8;     //minor
+    ptr[2] = mode;  //mode
+    ptr[3] = 0;     //flags
+}
+
+//Returns version as a 16-bit value. 0.8 -> 0x0008
+static inline uint16_t avpriv_codec2_version_from_extradata(uint8_t *ptr) {
+    return (ptr[0] << 8) + ptr[1];
+}
+
+static inline uint8_t avpriv_codec2_mode_from_extradata(uint8_t *ptr) {
+    return ptr[2];
+}
+
+#endif /* AVCODEC_CODEC2UTILS_H */