[FFmpeg-devel] [PATCH 3/4 v2] avcodec/aacdec: add support for channel configuration 14

[Andreas Rheinhardt]

James Almer:
> It corresponds to the 7.1(top) layout.
> 
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
>  libavcodec/aacdec_template.c | 23 ++++++++++++++++++++++-
>  libavcodec/aacdectab.h       |  6 +++---
>  libavcodec/mpeg4audio.c      |  5 +++--
>  libavcodec/mpeg4audio.h      |  2 +-
>  4 files changed, 29 insertions(+), 7 deletions(-)
> 
> diff --git a/libavcodec/aacdec_template.c b/libavcodec/aacdec_template.c
> index c10bc743b6..4b8e29ba71 100644
> --- a/libavcodec/aacdec_template.c
> +++ b/libavcodec/aacdec_template.c
> @@ -404,6 +404,21 @@ static uint64_t sniff_channel_order(uint8_t (*layout_map)[3], int tags)
>          i++;
>      }
>  
> +    // The previous checks would end up at 4 at this point for chan_config 14
> +    if (layout == AV_CH_LAYOUT_5POINT1 && tags == 5 && i == 4) {
> +        const uint8_t (*reference_layout_map)[3] = aac_channel_layout_map[13];
> +        for (int j = 0; j < tags; j++) {
> +            if (layout_map[j][0] != reference_layout_map[j][0] ||
> +                layout_map[j][2] != reference_layout_map[j][2])
> +                goto end_of_layout_definition;
> +        }
> +
> +        i += assign_pair(e2c_vec, layout_map, i,
> +                         AV_CH_TOP_FRONT_LEFT,
> +                         AV_CH_TOP_FRONT_RIGHT,
> +                         AAC_CHANNEL_FRONT,
> +                         &layout);
> +    }
>      // The previous checks would end up at 8 at this point for 22.2
>      if (layout == PREFIX_FOR_22POINT2 && tags == 16 && i == 8) {
>          const uint8_t (*reference_layout_map)[3] = aac_channel_layout_map[12];
> @@ -633,7 +648,7 @@ static int set_default_channel_config(AACContext *ac, AVCodecContext *avctx,
>                                        int channel_config)
>  {
>      if (channel_config < 1 || (channel_config > 7 && channel_config < 11) ||
> -        channel_config > 13) {
> +        channel_config > 14) {
>          av_log(avctx, AV_LOG_ERROR,
>                 "invalid default channel configuration (%d)\n",
>                 channel_config);
> @@ -717,6 +732,12 @@ static ChannelElement *get_che(AACContext *ac, int type, int elem_id)
>      /* For indexed channel configurations map the channels solely based
>       * on position. */
>      switch (ac->oc[1].m4ac.chan_config) {
> +    case 14:
> +        if (ac->tags_mapped > 2 && ((type == TYPE_CPE && elem_id < 3) ||
> +                                    (type == TYPE_LFE && elem_id < 1))) {
> +            ac->tags_mapped++;
> +            return ac->tag_che_map[type][elem_id] = ac->che[type][elem_id];
> +        }
>      case 13:
>          if (ac->tags_mapped > 3 && ((type == TYPE_CPE && elem_id < 8) ||
>                                      (type == TYPE_SCE && elem_id < 6) ||
> diff --git a/libavcodec/aacdectab.h b/libavcodec/aacdectab.h
> index b820f10556..e9bbd1fe13 100644
> --- a/libavcodec/aacdectab.h
> +++ b/libavcodec/aacdectab.h
> @@ -68,8 +68,8 @@ static const uint8_t aac_channel_layout_map[16][16][3] = {
>        { TYPE_SCE, 5, AAC_CHANNEL_FRONT }, // SCE6 = BtFC,
>        { TYPE_CPE, 7, AAC_CHANNEL_FRONT }, // CPE8 = BtFL and BtFR
>      },
> +    { { TYPE_SCE, 0, AAC_CHANNEL_FRONT }, { TYPE_CPE, 0, AAC_CHANNEL_FRONT }, { TYPE_CPE, 1, AAC_CHANNEL_SIDE }, { TYPE_LFE, 0, AAC_CHANNEL_LFE }, { TYPE_CPE, 2, AAC_CHANNEL_FRONT  }, },
>      { { 0, } },
> -    /* TODO: Add 7+1 TOP configuration */
>  };
>  
>  #if FF_API_OLD_CHANNEL_LAYOUT
> @@ -84,8 +84,8 @@ static const uint64_t aac_channel_layout[] = {
>      AV_CH_LAYOUT_6POINT1,
>      AV_CH_LAYOUT_7POINT1,
>      AV_CH_LAYOUT_22POINT2,
> +    AV_CH_LAYOUT_7POINT1_TOP,
>      0,
> -    /* AV_CH_LAYOUT_7POINT1_TOP, */
>  };
>  #endif
>  
> @@ -100,8 +100,8 @@ static const AVChannelLayout aac_ch_layout[] = {
>      AV_CHANNEL_LAYOUT_6POINT1,
>      AV_CHANNEL_LAYOUT_7POINT1,
>      AV_CHANNEL_LAYOUT_22POINT2,
> +    AV_CHANNEL_LAYOUT_7POINT1_TOP,
>      { 0 },
> -    /* AV_CHANNEL_LAYOUT_7POINT1_TOP, */
>  };
>  
>  #endif /* AVCODEC_AACDECTAB_H */
> diff --git a/libavcodec/mpeg4audio.c b/libavcodec/mpeg4audio.c
> index e38a8c0852..4a996411d1 100644
> --- a/libavcodec/mpeg4audio.c
> +++ b/libavcodec/mpeg4audio.c
> @@ -56,7 +56,7 @@ static int parse_config_ALS(GetBitContext *gb, MPEG4AudioConfig *c, void *logctx
>      return 0;
>  }
>  
> -const uint8_t ff_mpeg4audio_channels[14] = {
> +const uint8_t ff_mpeg4audio_channels[15] = {
>      0,
>      1, // mono (1/0)
>      2, // stereo (2/0)
> @@ -70,7 +70,8 @@ const uint8_t ff_mpeg4audio_channels[14] = {
>      0,
>      7, // 3/3.1
>      8, // 3/2/2.1
> -    24 // 3/3/3 - 5/2/3 - 3/0/0.2
> +    24, // 3/3/3 - 5/2/3 - 3/0/0.2
> +    8 // 3/2.1 - 2/0

Is it guaranteed that 8 will always be the last element of this array?
If not, you should use "8,", so that the comma won't have to be added
when someone makes an addition in the future.

>  };
>  
>  static inline int get_object_type(GetBitContext *gb)
> diff --git a/libavcodec/mpeg4audio.h b/libavcodec/mpeg4audio.h
> index a6f71cff58..56615ef321 100644
> --- a/libavcodec/mpeg4audio.h
> +++ b/libavcodec/mpeg4audio.h
> @@ -42,7 +42,7 @@ typedef struct MPEG4AudioConfig {
>  } MPEG4AudioConfig;
>  
>  extern const int     ff_mpeg4audio_sample_rates[16];
> -extern const uint8_t ff_mpeg4audio_channels[14];
> +extern const uint8_t ff_mpeg4audio_channels[15];
>  
>  /**
>   * Parse MPEG-4 systems extradata from a potentially unaligned GetBitContext to retrieve audio configuration.