[FFmpeg-trac] #2497(avcodec:open): ALAC encoder adds a burst of white noise

[FFmpeg]

#2497: ALAC encoder adds a burst of white noise
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             Reporter:  pneuman     |                    Owner:
                 Type:  defect      |                   Status:  open
             Priority:  normal      |                Component:  avcodec
              Version:  git-master  |               Resolution:
             Keywords:  alac        |               Blocked By:
             Blocking:              |  Reproduced by developer:  1
Analyzed by developer:  0           |
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Comment (by Cigaes):

 You should run with asserts enabled:
 {{{
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_s16le -> alac)
 Press [q] to stop, [?] for help
 Assertion n <= 31 && value < (1U << n) failed at libavcodec/put_bits.h:137
 }}}
 {{{
 #2  0x00002aaaab5f2219 in put_bits (value=<optimized out>, n=<optimized
 out>, s=<optimized out>) at libavcodec/put_bits.h:137
 #3  encode_scalar (s=s at entry=0x662e20, x=<optimized out>, k=<optimized
 out>, k at entry=7, write_sample_size=<optimized out>)
     at libavcodec/alacenc.c:115
 #4  0x00002aaaab5f2aec in alac_entropy_coder (s=0x662e20) at
 libavcodec/alacenc.c:333
 #5  write_element (s=0x662ea4, s at entry=0x662e20,
 element=element at entry=TYPE_CPE, instance=instance at entry=0,
     samples0=<optimized out>, samples1=<optimized out>) at
 libavcodec/alacenc.c:438
 #6  0x00002aaaab5f33ad in write_frame (s=s at entry=0x662e20,
 samples=0x634ce0,
     avpkt=<error reading variable: Unhandled dwarf expression opcode
 0xfa>,
     avpkt=<error reading variable: Unhandled dwarf expression opcode
 0xfa>) at libavcodec/alacenc.c:456
 #7  0x00002aaaab5f3559 in alac_encode_frame (avctx=0x6624a0,
 avpkt=0x7fffffffe180, frame=0x634ce0,
     got_packet_ptr=0x7fffffffe03c) at libavcodec/alacenc.c:628
 #8  0x00002aaaaba456db in avcodec_encode_audio2 (avctx=0x6624a0,
 avpkt=0x7fffffffe180, frame=0x634ce0,
     got_packet_ptr=0x7fffffffe03c) at libavcodec/utils.c:1532
 }}}

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Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2497#comment:4>
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