[FFmpeg-devel] [PATCH] lavf: add avs2 demuxer

[hwren]

Signed-off-by: hwren <hwrenx at 126.com>
---
 libavformat/Makefile     |  1 +
 libavformat/allformats.c |  1 +
 libavformat/davs2.c      | 64 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 66 insertions(+)
 create mode 100644 libavformat/davs2.c

diff --git a/libavformat/Makefile b/libavformat/Makefile
index f2f3aab..c4534b8 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -110,6 +110,7 @@ OBJS-$(CONFIG_AST_DEMUXER)               += ast.o astdec.o
 OBJS-$(CONFIG_AST_MUXER)                 += ast.o astenc.o
 OBJS-$(CONFIG_AU_DEMUXER)                += au.o pcm.o
 OBJS-$(CONFIG_AU_MUXER)                  += au.o rawenc.o
+OBJS-$(CONFIG_AVS2_DEMUXER)              += davs2.o rawdec.o
 OBJS-$(CONFIG_AVI_DEMUXER)               += avidec.o
 OBJS-$(CONFIG_AVI_MUXER)                 += avienc.o mpegtsenc.o avlanguage.o rawutils.o
 OBJS-$(CONFIG_AVM2_MUXER)                += swfenc.o swf.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index adcc8d9..38eaeea 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -76,6 +76,7 @@ extern AVInputFormat  ff_avisynth_demuxer;
 extern AVOutputFormat ff_avm2_muxer;
 extern AVInputFormat  ff_avr_demuxer;
 extern AVInputFormat  ff_avs_demuxer;
+extern AVInputFormat  ff_avs2_demuxer;
 extern AVInputFormat  ff_bethsoftvid_demuxer;
 extern AVInputFormat  ff_bfi_demuxer;
 extern AVInputFormat  ff_bintext_demuxer;
diff --git a/libavformat/davs2.c b/libavformat/davs2.c
new file mode 100644
index 0000000..8c90fd8
--- /dev/null
+++ b/libavformat/davs2.c
@@ -0,0 +1,64 @@
+/*
+ * AVS2 video stream probe.
+ *
+ * Copyright (C) 2018 Huiwen Ren, <hwrenx at 126.com>
+ *
+ * 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 "avformat.h"
+#include "rawdec.h"
+#include "libavcodec/internal.h"
+#include "libavutil/intreadwrite.h"
+
+#define ISSQH(x)  ((x) == 0xB0 )
+#define ISEND(x)  ((x) == 0xB1 )
+#define ISPIC(x)  ((x) == 0xB3 || (x) == 0xB6)
+#define ISUNIT(x) ( ISSQH(x) || ISEND(x) || (x) == 0xB2 || ISPIC(x) || (x) == 0xB5 || (x) == 0xB7 )
+#define ISAVS2(x) ((x) == 0x12 || (x) == 0x20 || (x) == 0x22 || (x) == 0x30 || (x) == 0x32 )
+
+static int avs2_probe(AVProbeData *p)
+{
+    uint32_t code= -1;
+    uint8_t state=0;
+    const uint8_t *ptr = p->buf, *end = p->buf + p->buf_size, *sqb=0;
+
+    while (ptr < end) {
+        ptr = avpriv_find_start_code(ptr, end, &code);
+        state = code & 0xFF;
+        if ((code & 0xffffff00) == 0x100) {
+            if (ISUNIT(state)) {
+                if (sqb) {
+                    break;
+                }
+                if (ISSQH(state)) {
+                    if (!ISAVS2(*ptr))
+                        return 0;
+                    sqb = ptr;
+                } else if (ISEND(state)) {
+                    return 0;
+                }
+            }
+        }
+    }
+    if (sqb && ptr-sqb >= 21){
+        return AVPROBE_SCORE_EXTENSION+2;
+    }
+    return 0;
+}
+
+FF_DEF_RAWVIDEO_DEMUXER(avs2, "raw AVS2-P2/IEEE 1857.4", avs2_probe, "avs,avs2", AV_CODEC_ID_AVS2)
-- 
2.7.4