[FFmpeg-devel] [PATCH v9 3/5] avformat/mov: Refactor mov_read_dvcc_dvvc to use ff_isom_parse_dvcc_dvvc

[lance.lmwang at gmail.com]

On Sun, Dec 05, 2021 at 06:35:33PM +0100, quietvoid wrote:
> To avoid duplicating code. The implementation in dovi_isom is identical.
> 
> Signed-off-by: quietvoid <tcChlisop0 at gmail.com>
> ---
>  libavformat/mov.c | 50 +++++++++--------------------------------------
>  1 file changed, 9 insertions(+), 41 deletions(-)
> 
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index 5c74d099da..b5f974fe05 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -55,6 +55,7 @@
>  #include "avformat.h"
>  #include "internal.h"
>  #include "avio_internal.h"
> +#include "dovi_isom.h"
>  #include "riff.h"
>  #include "isom.h"
>  #include "libavcodec/get_bits.h"
> @@ -7051,58 +7052,25 @@ static int mov_read_dmlp(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>  static int mov_read_dvcc_dvvc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>  {
>      AVStream *st;
> -    uint32_t buf;
> -    AVDOVIDecoderConfigurationRecord *dovi;
> -    size_t dovi_size;
> +    uint8_t buf[ISOM_DVCC_DVVC_SIZE + AV_INPUT_BUFFER_PADDING_SIZE];
>      int ret;
> +    int64_t read_size = atom.size;
>  
>      if (c->fc->nb_streams < 1)
>          return 0;
>      st = c->fc->streams[c->fc->nb_streams-1];
>  
> -    if ((uint64_t)atom.size > (1<<30) || atom.size < 4)
> -        return AVERROR_INVALIDDATA;
> -
> -    dovi = av_dovi_alloc(&dovi_size);
> -    if (!dovi)
> -        return AVERROR(ENOMEM);
> -
> -    dovi->dv_version_major = avio_r8(pb);
> -    dovi->dv_version_minor = avio_r8(pb);
> -
> -    buf = avio_rb16(pb);
> -    dovi->dv_profile        = (buf >> 9) & 0x7f;    // 7 bits
> -    dovi->dv_level          = (buf >> 3) & 0x3f;    // 6 bits
> -    dovi->rpu_present_flag  = (buf >> 2) & 0x01;    // 1 bit
> -    dovi->el_present_flag   = (buf >> 1) & 0x01;    // 1 bit
> -    dovi->bl_present_flag   =  buf       & 0x01;    // 1 bit
> -    if (atom.size >= 24) {  // 4 + 4 + 4 * 4
> -        buf = avio_r8(pb);
> -        dovi->dv_bl_signal_compatibility_id = (buf >> 4) & 0x0f; // 4 bits
> -    } else {
> -        // 0 stands for None
> -        // Dolby Vision V1.2.93 profiles and levels
> -        dovi->dv_bl_signal_compatibility_id = 0;
> +    // At most 24 bytes
> +    if (read_size > ISOM_DVCC_DVVC_SIZE) {
> +        read_size = ISOM_DVCC_DVVC_SIZE;
>      }
>  
> -    ret = av_stream_add_side_data(st, AV_PKT_DATA_DOVI_CONF,
> -                                  (uint8_t *)dovi, dovi_size);
> -    if (ret < 0) {
> -        av_free(dovi);
> +    if ((ret = avio_read(pb, buf, read_size)) < 0)
>          return ret;
> -    }
>  
> -    av_log(c, AV_LOG_TRACE, "DOVI in dvcC/dvvC/dvwC box, version: %d.%d, profile: %d, level: %d, "
> -           "rpu flag: %d, el flag: %d, bl flag: %d, compatibility id: %d\n",
> -           dovi->dv_version_major, dovi->dv_version_minor,
> -           dovi->dv_profile, dovi->dv_level,
> -           dovi->rpu_present_flag,
> -           dovi->el_present_flag,
> -           dovi->bl_present_flag,
> -           dovi->dv_bl_signal_compatibility_id
> -        );
> +    read_size = ret;

I prefer to check ret ! = read_size before like below:
if ((ret = avio_read(pb, buf, read_size)) != read_size)
    return ret < 0 ? ret : AVERROR(EIO);

>  
> -    return 0;
> +    return ff_isom_parse_dvcc_dvvc(c->fc, st, buf, read_size);
>  }
>  
>  static int mov_read_kind(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> -- 
> 2.34.1
> 
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-- 
Thanks,
Limin Wang