Crash when encoding fragments at lower resolution

[JDarnley]

I was trying to get a fragmented stream so I tried using 1280x720and fragment size of 10000 but I encountered the following crash. This is the same system as in my other issues. It can encode fine at 1080 with that fragment size and at 720 without fragments.

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Reading symbols from ./testprogs/vc2encode...done.
(gdb) r
Starting program: /home/james/src/vc2hqencode/testprogs/vc2encode --width=1280 --height=720 --fragment=10000
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
INFO: Processor Features:
INFO:   SSE4.2 [ ]
INFO:   AVX    [ ]
INFO:   AVX2   [ ]
INFO: VC2Encoder.cpp:283: Configuring for 1 threads, 4 jobs

[New Thread 0x7ffff66da700 (LWP 31741)]

Thread 1 "vc2encode" received signal SIGSEGV, Segmentation fault.
VC2Encoder::encodeData (this=0x555555825590, idata=<optimized out>, istride=<optimized out>, _odata=0x7fffffffd958, length=1152000, prev_parse_offset=prev_parse_offset@entry=0x7fffffffd954)
    at VC2Encoder.cpp:834
834           mEncoderData[k+1].odata[ 9] = (mEncoderData[k].final_offset >> 24)&0xFF;
(gdb) bt
#0  VC2Encoder::encodeData (this=0x555555825590, idata=<optimized out>, istride=<optimized out>, _odata=0x7fffffffd958, length=1152000,
    prev_parse_offset=prev_parse_offset@entry=0x7fffffffd954) at VC2Encoder.cpp:834
#1  0x0000555555573cc4 in vc2encode_encode_fragmented_data (handle=<optimized out>, idata=<optimized out>, istride=<optimized out>, odata=<optimized out>, length=<optimized out>,
    prev_parse_offset=<optimized out>, next_parse_offset=0x7fffffffd954) at vc2hqencode.cpp:138
#2  0x0000555555560f8b in main (argc=<optimized out>, argv=<optimized out>) at vc2encode.cpp:561

After building with --enable-debug something caught the error ad printed this.

(gdb) r
Starting program: /home/james/src/vc2hqencode/testprogs/vc2encode --width=1280 --height=720 --fragment=10000
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
INFO: Processor Features:
INFO:   SSE4.2 [ ]
INFO:   AVX    [ ]
INFO:   AVX2   [ ]
INFO: VC2Encoder.cpp:283: Configuring for 1 threads, 4 jobs

--------------------------------------------------------------------
   Sequence Header Coded Data
--------------------------------------------------------------------
      0x00000001/ 5  0x00000001/ 1  0x00000001/ 5  0x00000001/ 1
      0x0000002b/ 7  0x00000001/ 1  0x00020003/21  0x0000a203/19
      0x00000000/ 1  0x00000000/ 1  0x00000001/ 1  0x00000001/ 5
      0x00000000/ 1  0x00000000/ 1  0x00000000/ 1  0x00000000/ 1
      0x00000001/ 1
--------------------------------------------------------------------
--------------------------------------------------------------------
   Sequence Header Stream Data
--------------------------------------------------------------------
      42  42  43  44  00  00  00  00  17  00  00  00  00  0c  35  71
      00  01  8a  20  32  10  ff
--------------------------------------------------------------------
--------------------------------------------------------------------
   Picture Header Coded Data
--------------------------------------------------------------------
      0x00000001/ 3  0x00000001/ 5  0x00000000/ 1  0x00000000/ 1
      0x00000083/11  0x0000028b/13  0x00000001/ 1  0x00000003/ 3
      0x00000000/ 1
--------------------------------------------------------------------
--------------------------------------------------------------------
   Picture Header Stream Data
--------------------------------------------------------------------
      42  42  43  44  ec  00  00  00  00  00  00  00  00  00  00  00
      00  00  05  00  00  21  04  18  a2  ed
--------------------------------------------------------------------
ERROR: serialise.hpp:282:  coder overrun
Failed to encode picture
[Inferior 1 (process 27473) exited with code 01]