making act segmenter

1 files changed, 208 insertions, 0 deletions

diff --git a/ffmpeg/libavcodec/dca_parser.c b/ffmpeg/libavcodec/dca_parser.c
new file mode 100644
index 0000000..266520f
--- /dev/null
+++ b/ffmpeg/libavcodec/dca_parser.c
@@ -0,0 +1,208 @@
+/*
+ * DCA parser
+ * Copyright (C) 2004 Gildas Bazin
+ * Copyright (C) 2004 Benjamin Zores
+ * Copyright (C) 2006 Benjamin Larsson
+ * Copyright (C) 2007 Konstantin Shishkov
+ *
+ * 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 "parser.h"
+#include "dca.h"
+#include "dca_parser.h"
+#include "get_bits.h"
+#include "put_bits.h"
+
+typedef struct DCAParseContext {
+    ParseContext pc;
+    uint32_t lastmarker;
+    int size;
+    int framesize;
+    int hd_pos;
+} DCAParseContext;
+
+#define IS_MARKER(state, i, buf, buf_size) \
+ ((state == DCA_MARKER_14B_LE && (i < buf_size-2) && (buf[i+1] & 0xF0) == 0xF0 && buf[i+2] == 0x07) \
+ || (state == DCA_MARKER_14B_BE && (i < buf_size-2) && buf[i+1] == 0x07 && (buf[i+2] & 0xF0) == 0xF0) \
+ || state == DCA_MARKER_RAW_LE || state == DCA_MARKER_RAW_BE || state == DCA_HD_MARKER)
+
+/**
+ * Find the end of the current frame in the bitstream.
+ * @return the position of the first byte of the next frame, or -1
+ */
+static int dca_find_frame_end(DCAParseContext * pc1, const uint8_t * buf,
+                              int buf_size)
+{
+    int start_found, i;
+    uint32_t state;
+    ParseContext *pc = &pc1->pc;
+
+    start_found = pc->frame_start_found;
+    state = pc->state;
+
+    i = 0;
+    if (!start_found) {
+        for (i = 0; i < buf_size; i++) {
+            state = (state << 8) | buf[i];
+            if (IS_MARKER(state, i, buf, buf_size)) {
+                if (!pc1->lastmarker || state == pc1->lastmarker || pc1->lastmarker == DCA_HD_MARKER) {
+                    start_found = 1;
+                    pc1->lastmarker = state;
+                    break;
+                }
+            }
+        }
+    }
+    if (start_found) {
+        for (; i < buf_size; i++) {
+            pc1->size++;
+            state = (state << 8) | buf[i];
+            if (state == DCA_HD_MARKER && !pc1->hd_pos)
+                pc1->hd_pos = pc1->size;
+            if (IS_MARKER(state, i, buf, buf_size) && (state == pc1->lastmarker || pc1->lastmarker == DCA_HD_MARKER)) {
+                if(pc1->framesize > pc1->size)
+                    continue;
+                // We have to check that we really read a full frame here, and that it isn't a pure HD frame, because their size is not constant.
+                if(!pc1->framesize && state == pc1->lastmarker && state != DCA_HD_MARKER){
+                    pc1->framesize = pc1->hd_pos ? pc1->hd_pos : pc1->size;
+                }
+                pc->frame_start_found = 0;
+                pc->state = -1;
+                pc1->size = 0;
+                return i - 3;
+            }
+        }
+    }
+    pc->frame_start_found = start_found;
+    pc->state = state;
+    return END_NOT_FOUND;
+}
+
+static av_cold int dca_parse_init(AVCodecParserContext * s)
+{
+    DCAParseContext *pc1 = s->priv_data;
+
+    pc1->lastmarker = 0;
+    return 0;
+}
+
+int ff_dca_convert_bitstream(const uint8_t *src, int src_size, uint8_t *dst,
+                             int max_size)
+{
+    uint32_t mrk;
+    int i, tmp;
+    const uint16_t *ssrc = (const uint16_t *) src;
+    uint16_t *sdst = (uint16_t *) dst;
+    PutBitContext pb;
+
+    if ((unsigned) src_size > (unsigned) max_size)
+        src_size = max_size;
+
+    mrk = AV_RB32(src);
+    switch (mrk) {
+    case DCA_MARKER_RAW_BE:
+        memcpy(dst, src, src_size);
+        return src_size;
+    case DCA_MARKER_RAW_LE:
+        for (i = 0; i < (src_size + 1) >> 1; i++)
+            *sdst++ = av_bswap16(*ssrc++);
+        return src_size;
+    case DCA_MARKER_14B_BE:
+    case DCA_MARKER_14B_LE:
+        init_put_bits(&pb, dst, max_size);
+        for (i = 0; i < (src_size + 1) >> 1; i++, src += 2) {
+            tmp = ((mrk == DCA_MARKER_14B_BE) ? AV_RB16(src) : AV_RL16(src)) & 0x3FFF;
+            put_bits(&pb, 14, tmp);
+        }
+        flush_put_bits(&pb);
+        return (put_bits_count(&pb) + 7) >> 3;
+    default:
+        return AVERROR_INVALIDDATA;
+    }
+}
+
+static int dca_parse_params(const uint8_t *buf, int buf_size, int *duration,
+                            int *sample_rate)
+{
+    GetBitContext gb;
+    uint8_t hdr[12 + FF_INPUT_BUFFER_PADDING_SIZE] = { 0 };
+    int ret, sample_blocks, sr_code;
+
+    if (buf_size < 12)
+        return AVERROR_INVALIDDATA;
+
+    if ((ret = ff_dca_convert_bitstream(buf, 12, hdr, 12)) < 0)
+        return ret;
+
+    init_get_bits(&gb, hdr, 96);
+
+    skip_bits_long(&gb, 39);
+    sample_blocks = get_bits(&gb, 7) + 1;
+    if (sample_blocks < 8)
+        return AVERROR_INVALIDDATA;
+    *duration = 256 * (sample_blocks / 8);
+
+    skip_bits(&gb, 20);
+    sr_code = get_bits(&gb, 4);
+    *sample_rate = avpriv_dca_sample_rates[sr_code];
+    if (*sample_rate == 0)
+        return AVERROR_INVALIDDATA;
+
+    return 0;
+}
+
+static int dca_parse(AVCodecParserContext * s,
+                     AVCodecContext * avctx,
+                     const uint8_t ** poutbuf, int *poutbuf_size,
+                     const uint8_t * buf, int buf_size)
+{
+    DCAParseContext *pc1 = s->priv_data;
+    ParseContext *pc = &pc1->pc;
+    int next, duration, sample_rate;
+
+    if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
+        next = buf_size;
+    } else {
+        next = dca_find_frame_end(pc1, buf, buf_size);
+
+        if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
+            *poutbuf = NULL;
+            *poutbuf_size = 0;
+            return buf_size;
+        }
+    }
+
+    /* read the duration and sample rate from the frame header */
+    if (!dca_parse_params(buf, buf_size, &duration, &sample_rate)) {
+        s->duration = duration;
+        avctx->sample_rate = sample_rate;
+    } else
+        s->duration = 0;
+
+    *poutbuf = buf;
+    *poutbuf_size = buf_size;
+    return next;
+}
+
+AVCodecParser ff_dca_parser = {
+    .codec_ids      = { AV_CODEC_ID_DTS },
+    .priv_data_size = sizeof(DCAParseContext),
+    .parser_init    = dca_parse_init,
+    .parser_parse   = dca_parse,
+    .parser_close   = ff_parse_close,
+};