[FFmpeg-devel] [PATCH 36/39] avcodec/speedhqenc: Call correct function

[Andreas Rheinhardt]

Paul B Mahol:
> OK,
> 
> I guess encoding still works.
> 

Yes, it does. In fact, you need to enable either trellis or
quantizer_noise_shaping for it to make a difference. A quick test with
trellis on showed strange artifacts without this patch that are
eliminated by this patch; furthermore, the output is now reproducible.
So I'll apply this.

- Andreas

> On Thu, Dec 10, 2020 at 12:25 PM Andreas Rheinhardt <
> andreas.rheinhardt at gmail.com> wrote:
> 
>> Up until now, the SpeedHQ encoder called a wrong function for init:
>> void ff_init_uni_ac_vlc(const uint8_t huff_size_ac[256],
>>                         uint8_t *uni_ac_vlc_len);
>> Yet the first argument actually used is of type RLTable; the size of
>> said struct is less than 256 if the size of a pointer is four, leading
>> to an access beyond the end of the RLTable.
>>
>> This commit fixes this by calling the actually intended function:
>> init_uni_ac_vlc() from mpeg12enc.c. It was intended to use this
>> function [1], yet doing so was forgotten when the patch was actually
>> applied.
>>
>> [1]: https://ffmpeg.org/pipermail/ffmpeg-devel/2020-July/266187.html
>>
>> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
>> ---
>>  libavcodec/Makefile     |  2 +-
>>  libavcodec/mpeg12.h     |  1 +
>>  libavcodec/mpeg12enc.c  | 11 ++++++++---
>>  libavcodec/speedhqenc.c |  2 +-
>>  4 files changed, 11 insertions(+), 5 deletions(-)
>>
>> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
>> index 7f018e313b..450781886d 100644
>> --- a/libavcodec/Makefile
>> +++ b/libavcodec/Makefile
>> @@ -626,7 +626,7 @@ OBJS-$(CONFIG_SONIC_DECODER)           += sonic.o
>>  OBJS-$(CONFIG_SONIC_ENCODER)           += sonic.o
>>  OBJS-$(CONFIG_SONIC_LS_ENCODER)        += sonic.o
>>  OBJS-$(CONFIG_SPEEDHQ_DECODER)         += speedhq.o mpeg12.o mpeg12data.o
>> simple_idct.o
>> -OBJS-$(CONFIG_SPEEDHQ_ENCODER)         += speedhq.o mpeg12data.o
>> speedhqenc.o
>> +OBJS-$(CONFIG_SPEEDHQ_ENCODER)         += speedhq.o mpeg12data.o
>> mpeg12enc.o speedhqenc.o
>>  OBJS-$(CONFIG_SP5X_DECODER)            += sp5xdec.o
>>  OBJS-$(CONFIG_SRGC_DECODER)            += mscc.o
>>  OBJS-$(CONFIG_SRT_DECODER)             += srtdec.o ass.o htmlsubtitles.o
>> diff --git a/libavcodec/mpeg12.h b/libavcodec/mpeg12.h
>> index 76fc0bf955..4cd48b5d20 100644
>> --- a/libavcodec/mpeg12.h
>> +++ b/libavcodec/mpeg12.h
>> @@ -35,6 +35,7 @@ void ff_mpeg12_common_init(MpegEncContext *s);
>>  }
>>
>>  void ff_init_2d_vlc_rl(RLTable *rl, unsigned static_size, int flags);
>> +void ff_mpeg1_init_uni_ac_vlc(const RLTable *rl, uint8_t *uni_ac_vlc_len);
>>
>>  static inline int decode_dc(GetBitContext *gb, int component)
>>  {
>> diff --git a/libavcodec/mpeg12enc.c b/libavcodec/mpeg12enc.c
>> index e38cd074e1..a05c2db6cb 100644
>> --- a/libavcodec/mpeg12enc.c
>> +++ b/libavcodec/mpeg12enc.c
>> @@ -27,6 +27,7 @@
>>
>>  #include <stdint.h>
>>
>> +#include "config.h"
>>  #include "libavutil/attributes.h"
>>  #include "libavutil/avassert.h"
>>  #include "libavutil/log.h"
>> @@ -44,6 +45,7 @@
>>  #include "mpegvideo.h"
>>  #include "profiles.h"
>>
>> +#if CONFIG_MPEG1VIDEO_ENCODER || CONFIG_MPEG2VIDEO_ENCODER
>>  static const uint8_t svcd_scan_offset_placeholder[] = {
>>      0x10, 0x0E, 0x00, 0x80, 0x81, 0x00, 0x80,
>>      0x81, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
>> @@ -61,8 +63,9 @@ static uint32_t mpeg1_lum_dc_uni[512];
>>  static uint32_t mpeg1_chr_dc_uni[512];
>>
>>  #define A53_MAX_CC_COUNT 0x1f
>> +#endif /* CONFIG_MPEG1VIDEO_ENCODER || CONFIG_MPEG2VIDEO_ENCODER */
>>
>> -static av_cold void init_uni_ac_vlc(RLTable *rl, uint8_t *uni_ac_vlc_len)
>> +av_cold void ff_mpeg1_init_uni_ac_vlc(const RLTable *rl, uint8_t
>> *uni_ac_vlc_len)
>>  {
>>      int i;
>>
>> @@ -97,6 +100,7 @@ static av_cold void init_uni_ac_vlc(RLTable *rl,
>> uint8_t *uni_ac_vlc_len)
>>      }
>>  }
>>
>> +#if CONFIG_MPEG1VIDEO_ENCODER || CONFIG_MPEG2VIDEO_ENCODER
>>  static int find_frame_rate_index(MpegEncContext *s)
>>  {
>>      int i;
>> @@ -1039,8 +1043,8 @@ static av_cold void mpeg12_encode_init_static(void)
>>      ff_rl_init(&ff_rl_mpeg1, mpeg12_static_rl_table_store[0]);
>>      ff_rl_init(&ff_rl_mpeg2, mpeg12_static_rl_table_store[1]);
>>
>> -    init_uni_ac_vlc(&ff_rl_mpeg1, uni_mpeg1_ac_vlc_len);
>> -    init_uni_ac_vlc(&ff_rl_mpeg2, uni_mpeg2_ac_vlc_len);
>> +    ff_mpeg1_init_uni_ac_vlc(&ff_rl_mpeg1, uni_mpeg1_ac_vlc_len);
>> +    ff_mpeg1_init_uni_ac_vlc(&ff_rl_mpeg2, uni_mpeg2_ac_vlc_len);
>>
>>      /* build unified dc encoding tables */
>>      for (int i = -255; i < 256; i++) {
>> @@ -1216,3 +1220,4 @@ AVCodec ff_mpeg2video_encoder = {
>>      .caps_internal        = FF_CODEC_CAP_INIT_THREADSAFE |
>> FF_CODEC_CAP_INIT_CLEANUP,
>>      .priv_class           = &mpeg2_class,
>>  };
>> +#endif /* CONFIG_MPEG1VIDEO_ENCODER || CONFIG_MPEG2VIDEO_ENCODER */
>> diff --git a/libavcodec/speedhqenc.c b/libavcodec/speedhqenc.c
>> index 9807024980..a5bedd5301 100644
>> --- a/libavcodec/speedhqenc.c
>> +++ b/libavcodec/speedhqenc.c
>> @@ -96,7 +96,7 @@ static av_cold void speedhq_init_static_data(void)
>>          speedhq_chr_dc_uni[i + 255] = bits + (code << 8);
>>      }
>>
>> -    ff_init_uni_ac_vlc(&ff_rl_speedhq, uni_speedhq_ac_vlc_len);
>> +    ff_mpeg1_init_uni_ac_vlc(&ff_rl_speedhq, uni_speedhq_ac_vlc_len);
>>  }
>>
>>  av_cold int ff_speedhq_encode_init(MpegEncContext *s)
>> --
>> 2.25.1
>>