> On Jan 27, 2020, at 6:28 PM, Zhao Zhili <[email protected]> wrote: > > > >> On Jan 27, 2020, at 12:59 AM, Carl Eugen Hoyos <[email protected] >> <mailto:[email protected]>> wrote: >> >> Am So., 26. Jan. 2020 um 17:13 Uhr schrieb Zhao Zhili >> <[email protected] <mailto:[email protected]>>: >>> >>> --- >>> Or specify an upper limit on volume. What do you think? >>> >>> libavfilter/af_volume.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/libavfilter/af_volume.c b/libavfilter/af_volume.c >>> index 213c57195a..029925cbfb 100644 >>> --- a/libavfilter/af_volume.c >>> +++ b/libavfilter/af_volume.c >>> @@ -200,7 +200,7 @@ static inline void scale_samples_s16(uint8_t *dst, >>> const uint8_t *src, >>> int16_t *smp_dst = (int16_t *)dst; >>> const int16_t *smp_src = (const int16_t *)src; >>> for (i = 0; i < nb_samples; i++) >>> - smp_dst[i] = av_clip_int16(((int64_t)smp_src[i] * volume + 128) >> >>> 8); >>> + smp_dst[i] = (int16_t)av_clip64(((int64_t)smp_src[i] * volume + >>> 128) >> 8, INT16_MIN, INT16_MAX); >> >> The cast looks unnecessary and confusing but if a limit works, it is likely >> simpler imo. > > The function is supposed to handle smp_src[i] * volume > INT32_MAX, so the > cast is necessary. > > case AV_SAMPLE_FMT_S16: > if (vol->volume_i < 0x10000) > vol->scale_samples = scale_samples_s16_small; > else > vol->scale_samples = scale_samples_s16; > break; > > I'm not sure about the use case. Does the function suppose to handle > (((int64_t)smp_src[i] * volume + 128) >> 8) > INT32_MAX? > > By the way, there is another overflow in set_volume(): > > if (vol->precision == PRECISION_FIXED) { > vol->volume_i = (int)(vol->volume * 256 + 0.5); > vol->volume = vol->volume_i / 256.0; > av_log(ctx, AV_LOG_VERBOSE, "volume_i:%d/255 ", vol->volume_i); > }
Ping. Any suggestions? > >> >> Carl Eugen >> _______________________________________________ >> ffmpeg-devel mailing list >> [email protected] <mailto:[email protected]> >> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel >> <https://ffmpeg.org/mailman/listinfo/ffmpeg-devel> >> >> To unsubscribe, visit link above, or email >> [email protected] <mailto:[email protected]> >> with subject "unsubscribe". _______________________________________________ ffmpeg-devel mailing list [email protected] https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
