[FFmpeg-trac] #2686(avcodec:open): Native AAC encoder collapses at high bitrates on some samples

[FFmpeg]

#2686: Native AAC encoder collapses at high bitrates on some samples
-------------------------------------+-------------------------------------
             Reporter:  Kamedo2      |                    Owner:
                 Type:  defect       |                   Status:  open
             Priority:  normal       |                Component:  avcodec
              Version:  git-master   |               Resolution:
             Keywords:  aac          |               Blocked By:
  regression                         |  Reproduced by developer:  1
             Blocking:               |
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------

Comment (by Kamedo2):

 I think aacenc.c line 106 and 133 lacks the position for 7350Hz, which is
 in the 13th address.
 {{{
 static const uint8_t *swb_size_1024[] = {
     swb_size_1024_96, swb_size_1024_96, swb_size_1024_64,
     swb_size_1024_48, swb_size_1024_48, swb_size_1024_32,
     swb_size_1024_24, swb_size_1024_24, swb_size_1024_16,
     swb_size_1024_16, swb_size_1024_16, swb_size_1024_8
 };
 }}}
 {{{
 static const uint8_t *swb_size_128[] = {
     /* the last entry on the following row is swb_size_128_64 but is a
        duplicate of swb_size_128_96 */
     swb_size_128_96, swb_size_128_96, swb_size_128_96,
     swb_size_128_48, swb_size_128_48, swb_size_128_48,
     swb_size_128_24, swb_size_128_24, swb_size_128_16,
     swb_size_128_16, swb_size_128_16, swb_size_128_8
 };
 }}}
 aactab.c line 40 ~ 48 properly have the data for the 13th 7350Hz.
 {{{
 const uint8_t ff_aac_num_swb_1024[] = {
     41, 41, 47, 49, 49, 51, 47, 47, 43, 43, 43, 40, 40
 };

 const uint8_t ff_aac_num_swb_512[] = {
      0,  0,  0, 36, 36, 37, 31, 31,  0,  0,  0,  0,  0
 };

 const uint8_t ff_aac_num_swb_128[] = {
     12, 12, 12, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15
 };
 }}}

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Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2686#comment:202>
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