move mjpeg parser in its own file

Originally committed as revision 8987 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 101 insertions, 0 deletions

diff --git a/libavcodec/mjpeg_parser.c b/libavcodec/mjpeg_parser.c
new file mode 100644
index 0000000000..aad112eb9b
--- /dev/null
+++ b/libavcodec/mjpeg_parser.c
@@ -0,0 +1,101 @@
+/*
+ * MJPEG parser
+ * Copyright (c) 2000, 2001 Fabrice Bellard.
+ * Copyright (c) 2003 Alex Beregszaszi
+ * Copyright (c) 2003-2004 Michael Niedermayer
+ *
+ * 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 mjpeg_parser.c
+ * MJPEG parser.
+ */
+
+#include "parser.h"
+
+
+/**
+ * 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 find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){
+    int vop_found, i;
+    uint16_t state;
+
+    vop_found= pc->frame_start_found;
+    state= pc->state;
+
+    i=0;
+    if(!vop_found){
+        for(i=0; i<buf_size; i++){
+            state= (state<<8) | buf[i];
+            if(state == 0xFFD8){
+                i++;
+                vop_found=1;
+                break;
+            }
+        }
+    }
+
+    if(vop_found){
+        /* EOF considered as end of frame */
+        if (buf_size == 0)
+            return 0;
+        for(; i<buf_size; i++){
+            state= (state<<8) | buf[i];
+            if(state == 0xFFD8){
+                pc->frame_start_found=0;
+                pc->state=0;
+                return i-1;
+            }
+        }
+    }
+    pc->frame_start_found= vop_found;
+    pc->state= state;
+    return END_NOT_FOUND;
+}
+
+static int jpeg_parse(AVCodecParserContext *s,
+                           AVCodecContext *avctx,
+                           const uint8_t **poutbuf, int *poutbuf_size,
+                           const uint8_t *buf, int buf_size)
+{
+    ParseContext *pc = s->priv_data;
+    int next;
+
+    next= find_frame_end(pc, buf, buf_size);
+
+    if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
+        *poutbuf = NULL;
+        *poutbuf_size = 0;
+        return buf_size;
+    }
+
+    *poutbuf = buf;
+    *poutbuf_size = buf_size;
+    return next;
+}
+
+
+AVCodecParser mjpeg_parser = {
+    { CODEC_ID_MJPEG },
+    sizeof(ParseContext),
+    NULL,
+    jpeg_parse,
+    ff_parse_close,
+};