From 744472d2add12b115af2f5bcfb95d950c4a75989 Mon Sep 17 00:00:00 2001
From: Wim Taymans <wim.taymans@collabora.co.uk>
Date: Wed, 15 Dec 2010 16:22:54 +0100
Subject: [PATCH] j2kpay: cleanup header construction

Use a simpler way of constructing the header that doesn't depend on
the endianness.
---
 gst/rtp/gstrtpj2kpay.c | 68 +++++++++++++++++++++-----------------------------
 1 file changed, 29 insertions(+), 39 deletions(-)

diff --git a/gst/rtp/gstrtpj2kpay.c b/gst/rtp/gstrtpj2kpay.c
index 6fc129c..11e4e24 100644
--- a/gst/rtp/gstrtpj2kpay.c
+++ b/gst/rtp/gstrtpj2kpay.c
@@ -86,47 +86,18 @@ enum
   PROP_LAST
 };
 
-/*
- * RtpJ2KHeader:
- * @tp: type (0 progressive, 1 odd field, 2 even field)
- * @MHF: Main Header Flag
- * @mh_id: Main Header Identification
- * @T: Tile field invalidation flag
- * @priority: priority
- * @tile number: the tile number of the payload
- * @reserved: set to 0
- * @fragment offset: the byte offset of the current payload
- *
- *  0                   1                   2                   3
- *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * |tp |MHF|mh_id|T|     priority  |           tile number         |
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * |reserved       |             fragment offset                   |
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- */
 typedef struct
 {
-#if G_BYTE_ORDER == G_LITTLE_ENDIAN
-  guint T:1;
-  guint mh_id:3;
-  guint MHF:2;
-  guint tp:2;
-#elif G_BYTE_ORDER == G_BIG_ENDIAN
   guint tp:2;
   guint MHF:2;
   guint mh_id:3;
   guint T:1;
-#else
-#error "G_BYTE_ORDER should be big or little endian."
-#endif
   guint priority:8;
   guint tile:16;
-  guint reserved:8;
   guint offset:24;
 } RtpJ2KHeader;
 
-#define HEADER_SIZE sizeof(RtpJ2KHeader)
+#define HEADER_SIZE 8
 
 static void gst_rtp_j2k_pay_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec);
@@ -388,7 +359,6 @@ gst_rtp_j2k_pay_handle_buffer (GstBaseRTPPayload * basepayload,
   state.header.T = 1;           /* invalid tile */
   state.header.priority = 255;  /* always 255 for now */
   state.header.tile = 0;        /* no tile number */
-  state.header.reserved = 0;
   state.bitstream = FALSE;
   state.n_tiles = 0;
   state.next_sot = 0;
@@ -493,14 +463,34 @@ gst_rtp_j2k_pay_handle_buffer (GstBaseRTPPayload * basepayload,
           gst_rtp_buffer_set_marker (outbuf, TRUE);
       }
 
-      /* copy the header and push the packet */
-#if (G_BYTE_ORDER == G_LITTLE_ENDIAN)
-      state.header.offset = ((offset & 0x0000FF) << 16) |
-          ((offset & 0xFF0000) >> 16) | (offset & 0x00FF00);
-#else
-      state.header.offset = offset;
-#endif
-      memcpy (header, &state.header, HEADER_SIZE);
+      /*
+       * RtpJ2KHeader:
+       * @tp: type (0 progressive, 1 odd field, 2 even field)
+       * @MHF: Main Header Flag
+       * @mh_id: Main Header Identification
+       * @T: Tile field invalidation flag
+       * @priority: priority
+       * @tile number: the tile number of the payload
+       * @reserved: set to 0
+       * @fragment offset: the byte offset of the current payload
+       *
+       *  0                   1                   2                   3
+       *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+       * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+       * |tp |MHF|mh_id|T|     priority  |           tile number         |
+       * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+       * |reserved       |             fragment offset                   |
+       * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+       */
+      header[0] = (state.header.tp << 6) | (state.header.MHF << 4) |
+          (state.header.mh_id << 1) | state.header.T;
+      header[1] = state.header.priority;
+      header[2] = state.header.tile >> 8;
+      header[3] = state.header.tile & 0xff;
+      header[4] = 0;
+      header[5] = state.header.offset >> 16;
+      header[6] = (state.header.offset >> 8) & 0xff;
+      header[7] = state.header.offset & 0xff;
 
       if (pay->buffer_list) {
         GstBuffer *paybuf;
-- 
2.7.4