[FFmpeg-devel] [PATCH 3/4] avformat/mov_chan: respect channel order when parsing and creating chnl atom

[Marton Balint <cus@passwd.hu>]

Previously we always assumed that the channels are in native order, even if
they were not. The new channel layout API allows us to signal the proper
channel order, so let's do so.

Signed-off-by: Marton Balint <cus@passwd.hu>
---
 libavformat/mov_chan.c     | 145 +++++++++++++++++++++----------------
 libavformat/mov_chan.h     |   5 +-
 tests/ref/fate/mov-mp4-pcm |   2 +-
 3 files changed, 86 insertions(+), 66 deletions(-)

diff --git a/libavformat/mov_chan.c b/libavformat/mov_chan.c
index 9ee896f229..e3cef3f4e8 100644
--- a/libavformat/mov_chan.c
+++ b/libavformat/mov_chan.c
@@ -74,6 +74,46 @@ enum {
     c_Haptic = AV_CHAN_NONE,
 };
 
+enum {
+    iso_L    = AV_CHAN_FRONT_LEFT,
+    iso_R    = AV_CHAN_FRONT_RIGHT,
+    iso_C    = AV_CHAN_FRONT_CENTER,
+    iso_LFE  = AV_CHAN_LOW_FREQUENCY,
+    iso_Lsr  = AV_CHAN_BACK_LEFT,
+    iso_Rsr  = AV_CHAN_BACK_RIGHT,
+    iso_Lc   = AV_CHAN_FRONT_LEFT_OF_CENTER,
+    iso_Rc   = AV_CHAN_FRONT_RIGHT_OF_CENTER,
+    iso_Cs   = AV_CHAN_BACK_CENTER,
+    /* Side and surround are not exactly the same, but in order to have
+     * consistent 5.1/7.1 layouts we map them to the side channels. */
+    iso_Ls   = AV_CHAN_SIDE_LEFT,
+    iso_Lss  = AV_CHAN_SIDE_LEFT,
+    iso_Rs   = AV_CHAN_SIDE_RIGHT,
+    iso_Rss  = AV_CHAN_SIDE_RIGHT,
+    iso_Ts   = AV_CHAN_TOP_CENTER,
+    iso_Lv   = AV_CHAN_TOP_FRONT_LEFT,
+    iso_Cv   = AV_CHAN_TOP_FRONT_CENTER,
+    iso_Rv   = AV_CHAN_TOP_FRONT_RIGHT,
+    iso_Lvr  = AV_CHAN_TOP_BACK_LEFT,
+    iso_Cvr  = AV_CHAN_TOP_BACK_CENTER,
+    iso_Rvr  = AV_CHAN_TOP_BACK_RIGHT,
+    //       = AV_CHAN_STEREO_LEFT,
+    //       = AV_CHAN_STEREO_RIGHT,
+    iso_Lw   = AV_CHAN_WIDE_LEFT,
+    iso_Rw   = AV_CHAN_WIDE_RIGHT,
+    iso_Lsd  = AV_CHAN_SURROUND_DIRECT_LEFT,
+    iso_Rsd  = AV_CHAN_SURROUND_DIRECT_RIGHT,
+    iso_LFE2 = AV_CHAN_LOW_FREQUENCY_2,
+    iso_Lvss = AV_CHAN_TOP_SIDE_LEFT,
+    iso_Rvss = AV_CHAN_TOP_SIDE_RIGHT,
+    iso_Cb   = AV_CHAN_BOTTOM_FRONT_CENTER,
+    iso_Lb   = AV_CHAN_BOTTOM_FRONT_LEFT,
+    iso_Rb   = AV_CHAN_BOTTOM_FRONT_RIGHT,
+    /* The following have no exact counterparts */
+    iso_Lvs  = AV_CHAN_NONE,
+    iso_Rvs  = AV_CHAN_NONE,
+};
+
 struct MovChannelLayoutMap {
     union {
         uint32_t tag;
@@ -103,6 +143,10 @@ static int nonconst_expr(void) {
 #define CHLIST21(_tag, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, _20, _21) \
     CHLIST(_tag, 21, ID(_1),  ID(_2),  ID(_3),  ID(_4),  ID(_5),  ID(_6),  ID(_7),  ID(_8),  ID(_9),  ID(_10), \
                      ID(_11), ID(_12), ID(_13), ID(_14), ID(_15), ID(_16), ID(_17), ID(_18), ID(_19), ID(_20), ID(_21))
+#define CHLIST24(_tag, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, _20, _21, _22, _23, _24) \
+    CHLIST(_tag, 24, ID(_1),  ID(_2),  ID(_3),  ID(_4),  ID(_5),  ID(_6),  ID(_7),  ID(_8),  ID(_9),  ID(_10), \
+                     ID(_11), ID(_12), ID(_13), ID(_14), ID(_15), ID(_16), ID(_17), ID(_18), ID(_19), ID(_20), \
+                     ID(_21), ID(_22), ID(_23), ID(_24))
 
 static const struct MovChannelLayoutMap mov_ch_layout_map[] = {
     CHLIST01( MOV_CH_LAYOUT_MONO,                 C ),
@@ -190,6 +234,29 @@ static const struct MovChannelLayoutMap mov_ch_layout_map[] = {
     { {0} },
 };
 
+#undef ID
+#undef TAG
+#define ID(_0)            {.id = iso_##_0}
+#define TAG(_tag, _cnt)   {.tag = (_tag << 16) | _cnt}
+
+/* ISO/IEC 23001-8 */
+static const struct MovChannelLayoutMap iso_ch_layout_map[] = {
+    CHLIST01(  1,  C ),
+    CHLIST02(  2,  L,   R   ),
+    CHLIST03(  3,  C,   L,   R   ),
+    CHLIST04(  4,  C,   L,   R,    Cs  ),
+    CHLIST05(  5,  C,   L,   R,    Ls,   Rs  ),
+    CHLIST06(  6,  C,   L,   R,    Ls,   Rs,   LFE ),
+    CHLIST08(  7,  C,   Lc,  Rc,   L,    R,    Ls,   Rs,   LFE ),
+    CHLIST03(  9,  L,   R,   Cs  ),
+    CHLIST04( 10,  L,   R,   Ls,   Rs  ),
+    CHLIST07( 11,  C,   L,   R,    Ls,   Rs,   Cs,   LFE ),
+    CHLIST08( 12,  C,   L,   R,    Ls,   Rs,   Lsr,  Rsr,  LFE ),
+    CHLIST24( 13,  C,   Lc,  Rc,   L,    R,    Lss,  Rss,  Lsr,  Rsr,  Cs,  LFE,  LFE2,  Cv,  Lv,  Rv,  Lvss,  Rvss,  Ts,  Lvr,  Rvr,  Cvr,  Cb,  Lb,  Rb),
+    CHLIST08( 14,  C,   L,   R,    Ls,   Rs,   LFE,  Lv,   Rv),
+    { {0} },
+};
+
 static const enum MovChannelLayoutTag mov_ch_layouts_aac[] = {
     MOV_CH_LAYOUT_MONO,
     MOV_CH_LAYOUT_STEREO,
@@ -529,60 +596,6 @@ out:
     return ret;
 }
 
-/* ISO/IEC 23001-8, 8.2 */
-static const AVChannelLayout iso_channel_configuration[] = {
-    // 0: any setup
-    {0},
-
-    // 1: centre front
-    AV_CHANNEL_LAYOUT_MONO,
-
-    // 2: left front, right front
-    AV_CHANNEL_LAYOUT_STEREO,
-
-    // 3: centre front, left front, right front
-    AV_CHANNEL_LAYOUT_SURROUND,
-
-    // 4: centre front, left front, right front, rear centre
-    AV_CHANNEL_LAYOUT_4POINT0,
-
-    // 5: centre front, left front, right front, left surround, right surround
-    AV_CHANNEL_LAYOUT_5POINT0,
-
-    // 6: 5 + LFE
-    AV_CHANNEL_LAYOUT_5POINT1,
-
-    // 7: centre front, left front centre, right front centre,
-    // left front, right front, left surround, right surround, LFE
-    AV_CHANNEL_LAYOUT_7POINT1_WIDE,
-
-    // 8: channel1, channel2
-    AV_CHANNEL_LAYOUT_STEREO_DOWNMIX,
-
-    // 9: left front, right front, rear centre
-    AV_CHANNEL_LAYOUT_2_1,
-
-    // 10: left front, right front, left surround, right surround
-    AV_CHANNEL_LAYOUT_2_2,
-
-    // 11: centre front, left front, right front, left surround, right surround, rear centre, LFE
-    AV_CHANNEL_LAYOUT_6POINT1,
-
-    // 12: centre front, left front, right front
-    // left surround, right surround
-    // rear surround left, rear surround right
-    // LFE
-    AV_CHANNEL_LAYOUT_7POINT1,
-
-    // 13:
-    AV_CHANNEL_LAYOUT_22POINT2,
-
-    // 14:
-    AV_CHANNEL_LAYOUT_7POINT1_TOP_BACK,
-
-    // TODO: 15 - 20
-};
-
 /* ISO/IEC 23001-8, table 8 */
 static const enum AVChannel iso_channel_position[] = {
     // 0: left front
@@ -718,9 +731,9 @@ int ff_mov_get_channel_config_from_layout(const AVChannelLayout *layout, int *co
 {
     // Set default value which means any setup in 23001-8
     *config = 0;
-    for (int i = 0; i < FF_ARRAY_ELEMS(iso_channel_configuration); i++) {
-        if (!av_channel_layout_compare(layout, iso_channel_configuration + i)) {
-            *config = i;
+    for (int i = 0; iso_ch_layout_map[i].tag & 0xffff; i += 1 + (iso_ch_layout_map[i].tag & 0xffff)) {
+        if (is_layout_valid_for_tag(layout, iso_ch_layout_map[i].tag, &iso_ch_layout_map[i])) {
+            *config = iso_ch_layout_map[i].tag >> 16;
             break;
         }
     }
@@ -730,12 +743,16 @@ int ff_mov_get_channel_config_from_layout(const AVChannelLayout *layout, int *co
 
 int ff_mov_get_channel_layout_from_config(int config, AVChannelLayout *layout)
 {
-    if (config > 0 && config < FF_ARRAY_ELEMS(iso_channel_configuration)) {
-        av_channel_layout_copy(layout, &iso_channel_configuration[config]);
-        return 0;
-    }
+    if (config > 0) {
+        uint32_t layout_tag;
+
+        if (layout->nb_channels <= 0 || layout->nb_channels > UINT16_MAX)
+            return AVERROR_INVALIDDATA;
 
-    return -1;
+        layout_tag = (config << 16) | layout->nb_channels;
+        return mov_get_channel_layout(layout, layout_tag, iso_ch_layout_map);
+    }
+    return 1;
 }
 
 int ff_mov_get_channel_positions_from_layout(const AVChannelLayout *layout,
@@ -815,7 +832,9 @@ int ff_mov_read_chnl(AVFormatContext *s, AVIOContext *pb, AVStream *st)
                                       omitted_channel_map);
                 return AVERROR_PATCHWELCOME;
             }
-            ff_mov_get_channel_layout_from_config(layout, &st->codecpar->ch_layout);
+            ret = ff_mov_get_channel_layout_from_config(layout, &st->codecpar->ch_layout);
+            if (ret < 0)
+                return ret;
         }
     }
 
diff --git a/libavformat/mov_chan.h b/libavformat/mov_chan.h
index e480809c44..604395d7d3 100644
--- a/libavformat/mov_chan.h
+++ b/libavformat/mov_chan.h
@@ -172,9 +172,10 @@ int ff_mov_get_channel_config_from_layout(const AVChannelLayout *layout, int *co
 /**
  * Get AVChannelLayout from ISO/IEC 23001-8 ChannelConfiguration.
  *
- * @return 0 for success, -1 for doesn't match, layout is untouched on failure
+ * @return 1  if the config was unknown, layout is untouched in this case
+ *         0  if the config was found
+ *         <0 on error
  */
-
 int ff_mov_get_channel_layout_from_config(int config, AVChannelLayout *layout);
 
 /**
diff --git a/tests/ref/fate/mov-mp4-pcm b/tests/ref/fate/mov-mp4-pcm
index 6bae8f800b..19a978df95 100644
--- a/tests/ref/fate/mov-mp4-pcm
+++ b/tests/ref/fate/mov-mp4-pcm
@@ -1,4 +1,4 @@
-99ad26b4054794e84bd962a1124cdccf *tests/data/fate/mov-mp4-pcm.mp4
+462668dd69e7ce4fde4934d1d5978531 *tests/data/fate/mov-mp4-pcm.mp4
 10587977 tests/data/fate/mov-mp4-pcm.mp4
 #tb 0: 1/44100
 #media_type 0: audio
-- 
2.35.3

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