[FFmpeg-devel] [PATCH 16/16] vmdaudio: output 8-bit audio as AV_SAMPLE_FMT_U8.

Kostya kostya.shishkov
Wed Feb 23 20:02:55 CET 2011


On Wed, Feb 23, 2011 at 01:11:13PM -0500, Justin Ruggles wrote:
> 
> There is no need to expand to 16-bits. Just use memcpy() to copy the raw data.
> ---
>  libavcodec/vmdav.c        |   15 +-
>  tests/ref/fate/sierra-vmd |  372 ++++++++++++++++++++++----------------------
>  2 files changed, 193 insertions(+), 194 deletions(-)
> 

> diff --git a/libavcodec/vmdav.c b/libavcodec/vmdav.c
> index 88f674a..86e3683 100644
> --- a/libavcodec/vmdav.c
> +++ b/libavcodec/vmdav.c
> @@ -445,7 +445,10 @@ static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
>      VmdAudioContext *s = avctx->priv_data;
>  
>      s->avctx = avctx;
> -    avctx->sample_fmt = AV_SAMPLE_FMT_S16;
> +    if (avctx->bits_per_coded_sample == 16)
> +        avctx->sample_fmt = AV_SAMPLE_FMT_S16;
> +    else
> +        avctx->sample_fmt = AV_SAMPLE_FMT_U8;
>      s->out_bps = av_get_bits_per_sample_fmt(avctx->sample_fmt) >> 3;
>  
>      av_log(avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, "
> @@ -477,21 +480,17 @@ static void vmdaudio_decode_audio(VmdAudioContext *s, unsigned char *data,
>  static int vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data,
>      const uint8_t *buf, int silent_chunks, int data_size)
>  {
> -    int i;
>      int silent_size = s->avctx->block_align * silent_chunks * s->out_bps;
>  
>      if (silent_chunks) {
> -        memset(data, 0, silent_size);
> +        memset(data, s->out_bps == 2 ? 0x00 : 0x80, silent_size);
>          data += silent_size;
>      }
>      if (s->avctx->bits_per_coded_sample == 16)
>          vmdaudio_decode_audio(s, data, buf, data_size, s->avctx->channels == 2);
>      else {
> -        /* copy the data but convert it to signed */
> -        for (i = 0; i < data_size; i++){
> -            *data++ = buf[i] + 0x80;
> -            *data++ = buf[i] + 0x80;
> -        }
> +        /* just copy the data */
> +        memcpy(data, buf, data_size);
>      }
>  
>      return silent_size + data_size * s->out_bps;

ok



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