[FFmpeg-devel] [PATCH v2 2/7] avformat/mxf: get rid of samples per frame array usage

Marton Balint cus at passwd.hu
Thu Mar 5 23:56:23 EET 2020


Signed-off-by: Marton Balint <cus at passwd.hu>
---
 libavformat/mxf.c    | 44 ++++----------------------------------------
 libavformat/mxf.h    |  6 ------
 libavformat/mxfdec.c | 23 +++--------------------
 libavformat/mxfenc.c | 22 ++++++++++------------
 4 files changed, 17 insertions(+), 78 deletions(-)

diff --git a/libavformat/mxf.c b/libavformat/mxf.c
index 451cbcfb2c..10ccd770e3 100644
--- a/libavformat/mxf.c
+++ b/libavformat/mxf.c
@@ -131,16 +131,6 @@ int ff_mxf_decode_pixel_layout(const char pixel_layout[16], enum AVPixelFormat *
     return -1;
 }
 
-static const MXFSamplesPerFrame mxf_spf[] = {
-    { { 1001, 24000 }, { 2002, 0,    0,    0,    0,    0 } }, // FILM 23.976
-    { { 1, 24},        { 2000, 0,    0,    0,    0,    0 } }, // FILM 24
-    { { 1001, 30000 }, { 1602, 1601, 1602, 1601, 1602, 0 } }, // NTSC 29.97
-    { { 1001, 60000 }, { 801,  801,  800,  801,  801,  0 } }, // NTSC 59.94
-    { { 1, 25 },       { 1920, 0,    0,    0,    0,    0 } }, // PAL 25
-    { { 1, 50 },       { 960,  0,    0,    0,    0,    0 } }, // PAL 50
-    { { 1, 60 },       { 800,  0,    0,    0,    0,    0 } },
-};
-
 static const AVRational mxf_time_base[] = {
     { 1001, 24000 },
     { 1, 24},
@@ -152,40 +142,14 @@ static const AVRational mxf_time_base[] = {
     { 0, 0}
 };
 
-const MXFSamplesPerFrame *ff_mxf_get_samples_per_frame(AVFormatContext *s,
-                                                       AVRational time_base)
-{
-    int idx = av_find_nearest_q_idx(time_base, mxf_time_base);
-    AVRational diff = av_sub_q(time_base, mxf_time_base[idx]);
-
-    diff.num = FFABS(diff.num);
-
-    if (av_cmp_q(diff, (AVRational){1, 1000}) >= 0)
-        return NULL;
-
-    if (av_cmp_q(time_base, mxf_time_base[idx]))
-        av_log(s, AV_LOG_WARNING,
-               "%d/%d input time base matched %d/%d container time base\n",
-               time_base.num, time_base.den,
-               mxf_spf[idx].time_base.num,
-               mxf_spf[idx].time_base.den);
-
-    return &mxf_spf[idx];
-}
-
 static const int mxf_content_package_rates[] = {
     3, 2, 7, 13, 4, 10, 12,
 };
 
 int ff_mxf_get_content_package_rate(AVRational time_base)
 {
-    int idx = av_find_nearest_q_idx(time_base, mxf_time_base);
-    AVRational diff = av_sub_q(time_base, mxf_time_base[idx]);
-
-    diff.num = FFABS(diff.num);
-
-    if (av_cmp_q(diff, (AVRational){1, 1000}) >= 0)
-        return -1;
-
-    return mxf_content_package_rates[idx];
+    for (int i = 0; mxf_time_base[i].num; i++)
+        if (!av_cmp_q(time_base, mxf_time_base[i]))
+            return mxf_content_package_rates[i];
+    return 0;
 }
diff --git a/libavformat/mxf.h b/libavformat/mxf.h
index f32124f772..2669269830 100644
--- a/libavformat/mxf.h
+++ b/libavformat/mxf.h
@@ -82,18 +82,12 @@ typedef struct MXFCodecUL {
     MXFWrappingIndicatorType wrapping_indicator_type;
 } MXFCodecUL;
 
-typedef struct {
-    struct AVRational time_base;
-    int samples_per_frame[6];
-} MXFSamplesPerFrame;
-
 extern const MXFCodecUL ff_mxf_data_definition_uls[];
 extern const MXFCodecUL ff_mxf_codec_uls[];
 extern const MXFCodecUL ff_mxf_pixel_format_uls[];
 extern const MXFCodecUL ff_mxf_codec_tag_uls[];
 
 int ff_mxf_decode_pixel_layout(const char pixel_layout[16], enum AVPixelFormat *pix_fmt);
-const MXFSamplesPerFrame *ff_mxf_get_samples_per_frame(AVFormatContext *s, AVRational time_base);
 int ff_mxf_get_content_package_rate(AVRational time_base);
 
 
diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 9a48e2d2d1..9113e2a09c 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -3307,20 +3307,17 @@ static int mxf_get_next_track_edit_unit(MXFContext *mxf, MXFTrack *track, int64_
 static int64_t mxf_compute_sample_count(MXFContext *mxf, AVStream *st,
                                         int64_t edit_unit)
 {
-    int i, total = 0, size = 0;
     MXFTrack *track = st->priv_data;
     AVRational time_base = av_inv_q(track->edit_rate);
     AVRational sample_rate = av_inv_q(st->time_base);
-    const MXFSamplesPerFrame *spf = NULL;
-    int64_t sample_count;
 
     // For non-audio sample_count equals current edit unit
     if (st->codecpar->codec_type != AVMEDIA_TYPE_AUDIO)
         return edit_unit;
 
-    if ((sample_rate.num / sample_rate.den) == 48000)
-        spf = ff_mxf_get_samples_per_frame(mxf->fc, time_base);
-    if (!spf) {
+    if ((sample_rate.num / sample_rate.den) == 48000) {
+        return av_rescale_q(edit_unit, sample_rate, track->edit_rate);
+    } else {
         int remainder = (sample_rate.num * time_base.num) %
                         (time_base.den * sample_rate.den);
         if (remainder)
@@ -3331,20 +3328,6 @@ static int64_t mxf_compute_sample_count(MXFContext *mxf, AVStream *st,
                    sample_rate.num, sample_rate.den);
         return av_rescale_q(edit_unit, sample_rate, track->edit_rate);
     }
-
-    while (spf->samples_per_frame[size]) {
-        total += spf->samples_per_frame[size];
-        size++;
-    }
-
-    av_assert2(size);
-
-    sample_count = (edit_unit / size) * (uint64_t)total;
-    for (i = 0; i < edit_unit % size; i++) {
-        sample_count += spf->samples_per_frame[i];
-    }
-
-    return sample_count;
 }
 
 /**
diff --git a/libavformat/mxfenc.c b/libavformat/mxfenc.c
index bf7abe4f1c..93d840ebbf 100644
--- a/libavformat/mxfenc.c
+++ b/libavformat/mxfenc.c
@@ -2425,7 +2425,6 @@ static int mxf_write_header(AVFormatContext *s)
     MXFContext *mxf = s->priv_data;
     int i, ret;
     uint8_t present[FF_ARRAY_ELEMS(mxf_essence_container_uls)] = {0};
-    const MXFSamplesPerFrame *spf = NULL;
     int64_t timestamp = 0;
 
     if (!s->nb_streams)
@@ -2479,15 +2478,14 @@ static int mxf_write_header(AVFormatContext *s)
             case AVCHROMA_LOC_CENTER:  sc->color_siting = 3; break;
             }
 
-            mxf->timecode_base = (tbc.den + tbc.num/2) / tbc.num;
-            spf = ff_mxf_get_samples_per_frame(s, tbc);
-            if (!spf) {
+            mxf->content_package_rate = ff_mxf_get_content_package_rate(tbc);
+            if (!mxf->content_package_rate) {
                 av_log(s, AV_LOG_ERROR, "Unsupported video frame rate %d/%d\n",
                        tbc.den, tbc.num);
                 return AVERROR(EINVAL);
             }
-            mxf->content_package_rate = ff_mxf_get_content_package_rate(tbc);
-            mxf->time_base = spf->time_base;
+            mxf->timecode_base = (tbc.den + tbc.num/2) / tbc.num;
+            mxf->time_base = tbc;
             rate = av_inv_q(mxf->time_base);
             avpriv_set_pts_info(st, 64, mxf->time_base.num, mxf->time_base.den);
             if((ret = mxf_init_timecode(s, st, rate)) < 0)
@@ -2552,7 +2550,7 @@ static int mxf_write_header(AVFormatContext *s)
                 }
                 sc->index = INDEX_D10_AUDIO;
                 sc->container_ul = ((MXFStreamContext*)s->streams[0]->priv_data)->container_ul;
-                sc->frame_size = 4 + 8 * spf[0].samples_per_frame[0] * 4;
+                sc->frame_size = 4 + 8 * av_rescale_rnd(st->codecpar->sample_rate, mxf->time_base.num, mxf->time_base.den, AV_ROUND_UP) * 4;
             } else if (s->oformat == &ff_mxf_opatom_muxer) {
                 AVRational tbc = av_inv_q(mxf->audio_edit_rate);
 
@@ -2566,14 +2564,13 @@ static int mxf_write_header(AVFormatContext *s)
                     return AVERROR(EINVAL);
                 }
 
-                spf = ff_mxf_get_samples_per_frame(s, tbc);
-                if (!spf) {
+                if (!ff_mxf_get_content_package_rate(tbc)) {
                     av_log(s, AV_LOG_ERROR, "Unsupported timecode frame rate %d/%d\n", tbc.den, tbc.num);
                     return AVERROR(EINVAL);
                 }
 
                 mxf->time_base = st->time_base;
-                if((ret = mxf_init_timecode(s, st, av_inv_q(spf->time_base))) < 0)
+                if((ret = mxf_init_timecode(s, st, av_inv_q(tbc))) < 0)
                     return ret;
 
                 mxf->timecode_base = (tbc.den + tbc.num/2) / tbc.num;
@@ -2581,8 +2578,9 @@ static int mxf_write_header(AVFormatContext *s)
                 sc->index = INDEX_WAV;
             } else {
                 mxf->slice_count = 1;
-                sc->frame_size = (st->codecpar->channels * spf[0].samples_per_frame[0] *
-                                  av_get_bits_per_sample(st->codecpar->codec_id)) / 8;
+                sc->frame_size = st->codecpar->channels *
+                                 av_rescale_rnd(st->codecpar->sample_rate, mxf->time_base.num, mxf->time_base.den, AV_ROUND_UP) *
+                                 av_get_bits_per_sample(st->codecpar->codec_id) / 8;
             }
         } else if (st->codecpar->codec_type == AVMEDIA_TYPE_DATA) {
             AVDictionaryEntry *e = av_dict_get(st->metadata, "data_type", NULL, 0);
-- 
2.16.4



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