diff --git a/doc/filters.texi b/doc/filters.texi
index 1b1d13fa7f..d120082660 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -3625,7 +3625,7 @@ Default value is @var{auto}.
 
 @item mode
 Set the matching mode or strategy to use. @option{pc} mode is the safest in the
-sense that it wont risk creating jerkiness due to duplicate frames when
+sense that it won't risk creating jerkiness due to duplicate frames when
 possible, but if there are bad edits or blended fields it will end up
 outputting combed frames when a good match might actually exist. On the other
 hand, @option{pcn_ub} mode is the most risky in terms of creating jerkiness,
diff --git a/libavcodec/bmp.c b/libavcodec/bmp.c
index a3bb1a77d7..39d9f80385 100644
--- a/libavcodec/bmp.c
+++ b/libavcodec/bmp.c
@@ -244,7 +244,7 @@ static int bmp_decode_frame(AVCodecContext *avctx,
         // OS/2 bitmap, 3 bytes per palette entry
         if ((hsize-ihsize-14) < (colors << 2)) {
             if ((hsize-ihsize-14) < colors * 3) {
-                av_log(avctx, AV_LOG_ERROR, "palette doesnt fit in packet\n");
+                av_log(avctx, AV_LOG_ERROR, "palette doesn't fit in packet\n");
                 return AVERROR_INVALIDDATA;
             }
             for (i = 0; i < colors; i++)
diff --git a/libavcodec/imgconvert.c b/libavcodec/imgconvert.c
index e872035e39..6da531c658 100644
--- a/libavcodec/imgconvert.c
+++ b/libavcodec/imgconvert.c
@@ -148,7 +148,7 @@ static int get_pix_fmt_score(enum AVPixelFormat dst_pix_fmt,
             loss |= FF_LOSS_RESOLUTION;
             score -= 256 << dst_desc->log2_chroma_h;
         }
-        // dont favor 422 over 420 if downsampling is needed, because 420 has much better support on the decoder side
+        // don't favor 422 over 420 if downsampling is needed, because 420 has much better support on the decoder side
         if (dst_desc->log2_chroma_w == 1 && src_desc->log2_chroma_w == 0 &&
             dst_desc->log2_chroma_h == 1 && src_desc->log2_chroma_h == 0 ) {
             score += 512;
diff --git a/libavformat/act.c b/libavformat/act.c
index 78f1d3bb9a..3f223d57b6 100644
--- a/libavformat/act.c
+++ b/libavformat/act.c
@@ -42,7 +42,7 @@ static int probe(AVProbeData *p)
         (AV_RL32(&p->buf[16]) != 16))
     return 0;
 
-    //We cant be sure that this is ACT and not regular WAV
+    //We can't be sure that this is ACT and not regular WAV
     if (p->buf_size<512)
         return 0;
 
diff --git a/libavformat/hls.c b/libavformat/hls.c
index 7de6059c5a..95bbd45be6 100644
--- a/libavformat/hls.c
+++ b/libavformat/hls.c
@@ -218,7 +218,7 @@ static int parse_playlist(HLSContext *c, const char *url,
     if (!in) {
         AVDictionary *opts = NULL;
         close_in = 1;
-        /* Some HLS servers dont like being sent the range header */
+        /* Some HLS servers don't like being sent the range header */
         av_dict_set(&opts, "seekable", "0", 0);
 
         // broker prior HTTP options that should be consistent across requests
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index cff0760c0e..c18d8af2b6 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -87,7 +87,7 @@ static int64_t update_size(AVIOContext *pb, int64_t pos)
 
 static int supports_edts(MOVMuxContext *mov)
 {
-    // EDTS with fragments is tricky as we dont know the duration when its written
+    // EDTS with fragments is tricky as we don't know the duration when its written
     return (mov->use_editlist<0 && !(mov->flags & FF_MOV_FLAG_FRAGMENT)) || mov->use_editlist>0;
 }
 
diff --git a/libavformat/mpegtsenc.c b/libavformat/mpegtsenc.c
index d92fcb1d73..e7c522c8b9 100644
--- a/libavformat/mpegtsenc.c
+++ b/libavformat/mpegtsenc.c
@@ -119,7 +119,7 @@ static const AVOption options[] = {
     // backward compatibility
     { "resend_headers", "Reemit PAT/PMT before writing the next packet",
       offsetof(MpegTSWrite, reemit_pat_pmt), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},
-    { "mpegts_copyts", "dont offset dts/pts",
+    { "mpegts_copyts", "don't offset dts/pts",
       offsetof(MpegTSWrite, copyts), AV_OPT_TYPE_INT, {.i64=-1}, -1, 1, AV_OPT_FLAG_ENCODING_PARAM},
     { NULL },
 };
diff --git a/libavformat/options_table.h b/libavformat/options_table.h
index 9f8613764c..025554d614 100644
--- a/libavformat/options_table.h
+++ b/libavformat/options_table.h
@@ -45,7 +45,7 @@ static const AVOption options[]={
 {"igndts", "ignore dts", 0, AV_OPT_TYPE_CONST, {.i64 = AVFMT_FLAG_IGNDTS }, INT_MIN, INT_MAX, D, "fflags"},
 {"discardcorrupt", "discard corrupted frames", 0, AV_OPT_TYPE_CONST, {.i64 = AVFMT_FLAG_DISCARD_CORRUPT }, INT_MIN, INT_MAX, D, "fflags"},
 {"sortdts", "try to interleave outputted packets by dts", 0, AV_OPT_TYPE_CONST, {.i64 = AVFMT_FLAG_SORT_DTS }, INT_MIN, INT_MAX, D, "fflags"},
-{"keepside", "dont merge side data", 0, AV_OPT_TYPE_CONST, {.i64 = AVFMT_FLAG_KEEP_SIDE_DATA }, INT_MIN, INT_MAX, D, "fflags"},
+{"keepside", "don't merge side data", 0, AV_OPT_TYPE_CONST, {.i64 = AVFMT_FLAG_KEEP_SIDE_DATA }, INT_MIN, INT_MAX, D, "fflags"},
 {"latm", "enable RTP MP4A-LATM payload", 0, AV_OPT_TYPE_CONST, {.i64 = AVFMT_FLAG_MP4A_LATM }, INT_MIN, INT_MAX, E, "fflags"},
 {"nobuffer", "reduce the latency introduced by optional buffering", 0, AV_OPT_TYPE_CONST, {.i64 = AVFMT_FLAG_NOBUFFER }, 0, INT_MAX, D, "fflags"},
 {"seek2any", "forces seeking to enable seek to any mode", OFFSET(seek2any), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, D},
@@ -70,7 +70,7 @@ static const AVOption options[]={
 {"explode", "abort decoding on minor error detection", 0, AV_OPT_TYPE_CONST, {.i64 = AV_EF_EXPLODE }, INT_MIN, INT_MAX, D, "err_detect"},
 {"careful",    "consider things that violate the spec and have not been seen in the wild as errors", 0, AV_OPT_TYPE_CONST, {.i64 = AV_EF_CAREFUL }, INT_MIN, INT_MAX, D, "err_detect"},
 {"compliant",  "consider all spec non compliancies as errors", 0, AV_OPT_TYPE_CONST, {.i64 = AV_EF_COMPLIANT }, INT_MIN, INT_MAX, D, "err_detect"},
-{"aggressive", "consider things that a sane encoder shouldnt do as an error", 0, AV_OPT_TYPE_CONST, {.i64 = AV_EF_AGGRESSIVE }, INT_MIN, INT_MAX, D, "err_detect"},
+{"aggressive", "consider things that a sane encoder shouldn't do as an error", 0, AV_OPT_TYPE_CONST, {.i64 = AV_EF_AGGRESSIVE }, INT_MIN, INT_MAX, D, "err_detect"},
 {"use_wallclock_as_timestamps", "use wallclock as timestamps", OFFSET(use_wallclock_as_timestamps), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX-1, D},
 {"avoid_negative_ts", "shift timestamps to make them positive. 1 enables, 0 disables, default of -1 enables when required by target format.", OFFSET(avoid_negative_ts), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 1, E},
 {"skip_initial_bytes", "skip initial bytes", OFFSET(skip_initial_bytes), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX-1, D},
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 71fca24e6e..67fb97ce60 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -805,7 +805,7 @@ static int is_intra_only(AVCodecContext *enc){
 static int has_decode_delay_been_guessed(AVStream *st)
 {
     if(st->codec->codec_id != AV_CODEC_ID_H264) return 1;
-    if(!st->info) // if we have left find_stream_info then nb_decoded_frames wont increase anymore for stream copy
+    if(!st->info) // if we have left find_stream_info then nb_decoded_frames won't increase anymore for stream copy
         return 1;
 #if CONFIG_H264_DECODER
     if(st->codec->has_b_frames &&
diff --git a/libavutil/file.h b/libavutil/file.h
index b47ef8083d..a7364fe8fe 100644
--- a/libavutil/file.h
+++ b/libavutil/file.h
@@ -58,7 +58,7 @@ void av_file_unmap(uint8_t *bufptr, size_t size);
  * @return file descriptor of opened file (or -1 on error)
  * and opened file name in **filename.
  * @note On very old libcs it is necessary to set a secure umask before
- *       calling this, av_tempfile() cant call umask itself as it is used in
+ *       calling this, av_tempfile() can't call umask itself as it is used in
  *       libraries and could interfere with the calling application.
  */
 int av_tempfile(const char *prefix, char **filename, int log_offset, void *log_ctx);
diff --git a/libswresample/swresample.c b/libswresample/swresample.c
index 08b1aade4c..ba2afdb1d0 100644
--- a/libswresample/swresample.c
+++ b/libswresample/swresample.c
@@ -727,7 +727,7 @@ static int swr_convert_internal(struct SwrContext *s, AudioData *out, int out_co
             }
             s->dither.noise_pos += out_count;
         }
-//FIXME packed doesnt need more than 1 chan here!
+//FIXME packed doesn't need more than 1 chan here!
         swri_audio_convert(s->out_convert, out, conv_src, out_count);
     }
     return out_count;
@@ -747,7 +747,7 @@ int swr_convert(struct SwrContext *s, uint8_t *out_arg[SWR_CH_MAX], int out_coun
 
         reversefill_audiodata(&s->drop_temp, tmp_arg);
         s->drop_output *= -1; //FIXME find a less hackish solution
-        ret = swr_convert(s, tmp_arg, FFMIN(-s->drop_output, MAX_DROP_STEP), in_arg, in_count); //FIXME optimize but this is as good as never called so maybe it doesnt matter
+        ret = swr_convert(s, tmp_arg, FFMIN(-s->drop_output, MAX_DROP_STEP), in_arg, in_count); //FIXME optimize but this is as good as never called so maybe it doesn't matter
         s->drop_output *= -1;
         in_count = 0;
         if(ret>0) {