1 files changed, 134 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/mjpeg_parser.c b/ffmpeg/libavcodec/mjpeg_parser.c
new file mode 100644
index 0000000..e548b00
--- /dev/null
+++ b/ffmpeg/libavcodec/mjpeg_parser.c
@@ -0,0 +1,134 @@
+/*
+ * 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.
+ */
+
+#include "parser.h"
+
+typedef struct MJPEGParserContext{
+    ParseContext pc;
+    int size;
+}MJPEGParserContext;
+
+/**
+ * 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 find_frame_end(MJPEGParserContext *m, const uint8_t *buf, int buf_size){
+    ParseContext *pc= &m->pc;
+    int vop_found, i;
+    uint32_t state;
+
+    vop_found= pc->frame_start_found;
+    state= pc->state;
+
+    i=0;
+    if(!vop_found){
+        for(i=0; i<buf_size;){
+            state= (state<<8) | buf[i];
+            if(state>=0xFFC00000 && state<=0xFFFEFFFF){
+                if(state>=0xFFD80000 && state<=0xFFD8FFFF){
+                    i++;
+                    vop_found=1;
+                    break;
+                }else if(state<0xFFD00000 || state>0xFFD9FFFF){
+                    m->size= (state&0xFFFF)-1;
+                }
+            }
+            if(m->size>0){
+                int size= FFMIN(buf_size-i, m->size);
+                i+=size;
+                m->size-=size;
+                state=0;
+                continue;
+            }else
+                i++;
+        }
+    }
+
+    if(vop_found){
+        /* EOF considered as end of frame */
+        if (buf_size == 0)
+            return 0;
+        for(; i<buf_size;){
+            state= (state<<8) | buf[i];
+            if(state>=0xFFC00000 && state<=0xFFFEFFFF){
+                if(state>=0xFFD80000 && state<=0xFFD8FFFF){
+                    pc->frame_start_found=0;
+                    pc->state=0;
+                    return i-3;
+                } else if(state<0xFFD00000 || state>0xFFD9FFFF){
+                    m->size= (state&0xFFFF)-1;
+                }
+            }
+            if(m->size>0){
+                int size= FFMIN(buf_size-i, m->size);
+                i+=size;
+                m->size-=size;
+                state=0;
+                continue;
+            }else
+                i++;
+        }
+    }
+    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)
+{
+    MJPEGParserContext *m = s->priv_data;
+    ParseContext *pc = &m->pc;
+    int next;
+
+    if(s->flags & PARSER_FLAG_COMPLETE_FRAMES){
+        next= buf_size;
+    }else{
+        next= find_frame_end(m, 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 ff_mjpeg_parser = {
+    .codec_ids      = { AV_CODEC_ID_MJPEG },
+    .priv_data_size = sizeof(MJPEGParserContext),
+    .parser_parse   = jpeg_parse,
+    .parser_close   = ff_parse_close,
+};