Move dca parser to its own file.

Originally committed as revision 8881 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 127 insertions, 0 deletions

diff --git a/libavcodec/dca_parser.c b/libavcodec/dca_parser.c
new file mode 100644
index 0000000000..db66b474f3
--- /dev/null
+++ b/libavcodec/dca_parser.c
@@ -0,0 +1,127 @@
+/*
+ * 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
+ */
+
+/**
+ * @file dca_parser.c
+ */
+
+#include "avcodec.h"
+#include "parser.h"
+#include "dca.h"
+
+typedef struct DCAParseContext {
+    ParseContext pc;
+    uint32_t lastmarker;
+} 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)
+
+/**
+ * finds 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) {
+                    start_found = 1;
+                    break;
+                } else if (!pc1->lastmarker) {
+                    start_found = 1;
+                    pc1->lastmarker = state;
+                    break;
+                }
+            }
+        }
+    }
+    if (start_found) {
+        for (; i < buf_size; i++) {
+            state = (state << 8) | buf[i];
+            if (state == pc1->lastmarker && IS_MARKER(state, i, buf, buf_size)) {
+                pc->frame_start_found = 0;
+                pc->state = -1;
+                return i - 3;
+            }
+        }
+    }
+    pc->frame_start_found = start_found;
+    pc->state = state;
+    return END_NOT_FOUND;
+}
+
+static int dca_parse_init(AVCodecParserContext * s)
+{
+    DCAParseContext *pc1 = s->priv_data;
+
+    pc1->lastmarker = 0;
+    return 0;
+}
+
+static int dca_parse(AVCodecParserContext * s,
+                     AVCodecContext * avctx,
+                     uint8_t ** poutbuf, int *poutbuf_size,
+                     const uint8_t * buf, int buf_size)
+{
+    DCAParseContext *pc1 = s->priv_data;
+    ParseContext *pc = &pc1->pc;
+    int next;
+
+    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, (uint8_t **) & buf, &buf_size) < 0) {
+            *poutbuf = NULL;
+            *poutbuf_size = 0;
+            return buf_size;
+        }
+    }
+    *poutbuf = (uint8_t *) buf;
+    *poutbuf_size = buf_size;
+    return next;
+}
+
+AVCodecParser dca_parser = {
+    {CODEC_ID_DTS},
+    sizeof(DCAParseContext),
+    dca_parse_init,
+    dca_parse,
+    ff_parse_close,
+};