[opus] Initial implementation of ch.mapping 253/3

Mon Jun 12 16:34:49 UTC 2017

apologies, this is the correct patch I meant to send:

On Mon, Jun 12, 2017 at 9:19 AM Drew Allen <bitllama at google.com> wrote:

> Thanks again Mark for taking a look and pointing out the issues that
> previous patch had. I've addressed your concerns. The tests should no
> longer give any warnings or errors regarding usage or c89. I've ensured the
> memory issues have also been addressed.
>
> Please let me know any and all other concerns as well. :)
>
> Attached is the new proposed patch.
>
> Cheers,
> Drew
>
> On Wed, Jun 7, 2017 at 8:02 AM Drew Allen <bitllama at google.com> wrote:
>
>> Thanks for looking over this, Mark! I'm travelling this week but when I'm
>> back I'll address all of your concerns and send,out another patch. :)
>>
>> On Jun 7, 2017 9:56 AM, "Mark Harris" <mark.hsj at gmail.com> wrote:
>>
>>> On Tue, May 30, 2017 at 3:13 PM, Drew Allen <bitllama at google.com> wrote:
>>> > Hello all,
>>> >
>>> > Attached is the initial proposed implementation for ch.mapping 253/3,
>>> based
>>> > on the IETF proposal:
>>> > https://tools.ietf.org/html/draft-ietf-codec-ambisonics-03
>>> >
>>> > A brief overview of the patch, as it is slightly lengthy:
>>> > After discussion with Jean-Marc, we determined that ch.253/3 will need
>>> the
>>> > demixing matrix as part of the encoder/decoder struct stack and thus
>>> will
>>> > require a new Encoder/Decoder structure. For this, I've proposed
>>> > OpusPEnc/OpusPDec (for "projection"), which wraps OpusMSEnc/OpusMSDec
>>> aside
>>> > from the addition of the mixing matrix structure. The functionality
>>> also
>>> > wraps the functionality of the multistream API aside from matrix
>>> transforms
>>> > during encode/decode.
>>> >
>>> > We have included 3 mixing/demixing matrix pairs that are sufficient for
>>> > coding/decoding 1st/2nd/3rd order content respecitvely.
>>> >
>>> > I've modified the multistream api slightly, first to include some
>>> > supplemental API extensions to allow wrapping and moved the
>>> declaration of
>>> > the MSEnc/MSDec to opus_private so that the projection API can compile.
>>> >
>>> > Some basic tests to ensure matrix multiplication and encoding/decoding
>>> using
>>> > projection has been included.
>>> >
>>> > I am of course happy and eager to take any and all
>>> > suggestions/comments/questions/recommendations regarding the patch,
>>> > including naming conventions/style/etc.
>>> >
>>> > Looking forward to your feedback,
>>> >
>>> > Cheers,
>>> > Drew
>>>
>>>
>>> Hi Drew,
>>>
>>> I ran into some issues with this new test.
>>>
>>> Building the test for floating point produces a clang compiler warning:
>>>
>>>   CC       tests/test_opus_projection.o
>>> tests/test_opus_projection.c:137:9: warning: using floating point
>>> absolute value function
>>>       'fabs' when argument is of integer type [-Wabsolute-value]
>>>     if (ABS16(a[i] - b[i]) > tolerance)
>>>         ^
>>> ./celt/arch.h:194:26: note: expanded from macro 'ABS16'
>>> #define ABS16(x) ((float)fabs(x))
>>>                          ^
>>> tests/test_opus_projection.c:137:9: note: use function 'abs' instead
>>> ./celt/arch.h:194:26: note: expanded from macro 'ABS16'
>>> #define ABS16(x) ((float)fabs(x))
>>>                          ^
>>>
>>> Also the test fails to compile with -std=c89:
>>>
>>> tests/test_opus_projection.c:57:1: error: C++ style comments are not
>>> allowed in ISO C90
>>>  // static const MappingMatrix test_matrix = {
>>>  ^
>>> tests/test_opus_projection.c:57:1: error: (this will be reported only
>>> once per input file)
>>> tests/test_opus_projection.c: In function 'main':
>>> tests/test_opus_projection.c:403:1: warning: control reaches end of
>>> non-void function [-Wreturn-type]
>>>  }
>>>  ^
>>>
>>> Running the test, an issue occurs in test_creation_arguments().
>>> opus_projection_ambisonics_encoder_create() is intentionally called
>>> with invalid arguments (initially, channels=0), which causes an error
>>> to be returned and streams and coupled_streams are left uninitialized.
>>> These uninitialized values are passed to
>>> opus_projection_decoder_create(), which does not check that the
>>> arguments are not too large before using them to attempt allocation of
>>> a ridiculous amount of memory.  Results may vary depending on the
>>> uninitialized values of streams and coupled_streams.  Valgrind reports
>>> several uses of uninitialized values such as:
>>>
>>>  Conditional jump or move depends on uninitialised value(s)
>>>     at 0x100067B72: opus_multistream_decoder_get_size
>>> (opus_multistream_decoder.c:47)
>>>     by 0x10006B098: opus_projection_decoder_get_size
>>> (opus_projection_decoder.c:54)
>>>     by 0x10006B136: opus_projection_decoder_create
>>> (opus_projection_decoder.c:68)
>>>     by 0x10000140D: test_creation_arguments (test_opus_projection.c:273)
>>>     by 0x100001D06: main (test_opus_projection.c:396)
>>>   Uninitialised value was created by a stack allocation
>>>     at 0x100001330: test_creation_arguments (test_opus_projection.c:252)
>>>
>>> Additionally, the demixing_matrix appears to be used uninitialized
>>> when order_plus_one is 1 (or greater than 4):
>>>
>>>  Conditional jump or move depends on uninitialised value(s)
>>>     at 0x10006A6DF: opus_projection_encoder_init_impl
>>> (opus_projection_encoder.c:125)
>>>     by 0x10006A9CA: opus_projection_ambisonics_encoder_init
>>> (opus_projection_encoder.c:196)
>>>     by 0x10006AC7B: opus_projection_ambisonics_encoder_create
>>> (opus_projection_encoder.c:261)
>>>     by 0x1000013D9: test_creation_arguments (test_opus_projection.c:268)
>>>     by 0x100001D06: main (test_opus_projection.c:396)
>>>   Uninitialised value was created by a heap allocation
>>>     at 0x10010FE71: malloc (vg_replace_malloc.c:302)
>>>     by 0x10006AB84: opus_alloc (os_support.h:49)
>>>     by 0x10006AC1F: opus_projection_ambisonics_encoder_create
>>> (opus_projection_encoder.c:252)
>>>     by 0x1000013D9: test_creation_arguments (test_opus_projection.c:268)
>>>     by 0x100001D06: main (test_opus_projection.c:396)
>>>
>>> Another issue occurs in mapping_matrix_dot_short().  It attempts to
>>> read beyond the end of the input buffer and may cause a segmentation
>>> fault.  It appears that the input buffer contains only 2 channels of
>>> 480 samples each, but 16 channels of 960 samples each are being read
>>> from the buffer.  Valgrind reports the following:
>>>
>>>  Invalid read of size 2
>>>     at 0x10006B9D8: mapping_matrix_dot_short (mapping_matrix.c:98)
>>>     by 0x10006BABD: mapping_matrix_multiply_short (mapping_matrix.c:119)
>>>     by 0x10006AD5B: opus_projection_encode
>>> (opus_projection_encoder.c:283)
>>>     by 0x100001BCB: test_encode_decode (test_opus_projection.c:374)
>>>     by 0x100001D2D: main (test_opus_projection.c:400)
>>>   Address 0x10490b000 is not stack'd, malloc'd or (recently) free'd
>>>
>>>  Process terminating with default action of signal 11 (SIGSEGV)
>>>   Access not within mapped region at address 0x10490B000
>>>     at 0x10006B9D8: mapping_matrix_dot_short (mapping_matrix.c:98)
>>>     by 0x10006BABD: mapping_matrix_multiply_short (mapping_matrix.c:119)
>>>     by 0x10006AD5B: opus_projection_encode
>>> (opus_projection_encoder.c:283)
>>>     by 0x100001BCB: test_encode_decode (test_opus_projection.c:374)
>>>     by 0x100001D2D: main (test_opus_projection.c:400)
>>>
>>>  - Mark
>>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.xiph.org/pipermail/opus/attachments/20170612/d1128837/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Support-for-Ch.253-Using-OpusPDec-OpusPEnc-structs.patch
Type: text/x-patch
Size: 60103 bytes
Desc: not available
URL: <http://lists.xiph.org/pipermail/opus/attachments/20170612/d1128837/attachment-0001.bin>