[FFmpeg-devel] [PATCH 16/23] lavc/movtextenc: init style record from ASS dialog style

[Philip Langdale]

On Mon, 6 Apr 2020 11:52:11 -0600
John Stebbins <jstebbins at jetheaddev.com> wrote:

> ---
>  libavcodec/movtextenc.c | 60
> ++++++++++++++++++++++++++++++++++------- 1 file changed, 50
> insertions(+), 10 deletions(-)
> 
> diff --git a/libavcodec/movtextenc.c b/libavcodec/movtextenc.c
> index d389111419..4e7d55efcb 100644
> --- a/libavcodec/movtextenc.c
> +++ b/libavcodec/movtextenc.c
> @@ -39,6 +39,11 @@
>  #define HLIT_BOX   (1<<1)
>  #define HCLR_BOX   (1<<2)
>  
> +#define DEFAULT_STYLE_FONT_ID  0x01
> +#define DEFAULT_STYLE_FONTSIZE 0x12
> +#define DEFAULT_STYLE_COLOR    0xffffffff
> +#define DEFAULT_STYLE_FLAG     0x00
> +
>  #define BGR_TO_RGB(c) (((c) & 0xff) << 16 | ((c) & 0xff00) | (((c)
> >> 16) & 0xff)) #define av_bprint_append_any(buf, data, size)
> >> av_bprint_append_data(buf, ((const char*)data), size)
>  
> @@ -46,6 +51,9 @@ typedef struct {
>      uint16_t style_start;
>      uint16_t style_end;
>      uint8_t style_flag;
> +    uint16_t style_fontID;
> +    uint8_t style_fontsize;
> +    uint32_t style_color;
>  } StyleBox;
>  
>  typedef struct {
> @@ -68,9 +76,7 @@ typedef struct {
>      HilightcolorBox hclr;
>      int count;
>      uint8_t box_flags;
> -    uint16_t style_fontID;
> -    uint8_t style_fontsize;
> -    uint32_t style_color;
> +    StyleBox d;
>      uint16_t text_pos;
>      uint16_t byte_count;
>  } MovTextContext;
> @@ -104,25 +110,26 @@ static void encode_styl(MovTextContext *s,
> uint32_t tsmb_type) tsmb_size = s->count * STYLE_RECORD_SIZE +
> SIZE_ADD; tsmb_size = AV_RB32(&tsmb_size);
>          style_entries = AV_RB16(&s->count);
> -        s->style_fontID = 0x00 | 0x01<<8;
> -        s->style_fontsize = 0x12;
> -        s->style_color = MKTAG(0xFF, 0xFF, 0xFF, 0xFF);
>          /*The above three attributes are hard coded for now
>          but will come from ASS style in the future*/
>          av_bprint_append_any(&s->buffer, &tsmb_size, 4);
>          av_bprint_append_any(&s->buffer, &tsmb_type, 4);
>          av_bprint_append_any(&s->buffer, &style_entries, 2);
>          for (j = 0; j < s->count; j++) {
> -            uint16_t style_start, style_end;
> +            uint16_t style_start, style_end, style_fontID;
> +            uint32_t style_color;
>  
>              style_start  =
> AV_RB16(&s->style_attributes[j]->style_start); style_end    =
> AV_RB16(&s->style_attributes[j]->style_end);
> +            style_color  = AV_RB32(&s->d.style_color);
> +            style_fontID = AV_RB16(&s->d.style_fontID);
> +
>              av_bprint_append_any(&s->buffer, &style_start, 2);
>              av_bprint_append_any(&s->buffer, &style_end, 2);
> -            av_bprint_append_any(&s->buffer, &s->style_fontID, 2);
> +            av_bprint_append_any(&s->buffer, &style_fontID, 2);
>              av_bprint_append_any(&s->buffer,
> &s->style_attributes[j]->style_flag, 1);
> -            av_bprint_append_any(&s->buffer, &s->style_fontsize, 1);
> -            av_bprint_append_any(&s->buffer, &s->style_color, 4);
> +            av_bprint_append_any(&s->buffer, &s->d.style_fontsize,
> 1);
> +            av_bprint_append_any(&s->buffer, &style_color, 4);
>          }
>      }
>      mov_text_cleanup(s);
> @@ -220,6 +227,13 @@ static av_cold int
> mov_text_encode_init(AVCodecContext *avctx) memcpy(avctx->extradata,
> text_sample_entry, avctx->extradata_size); 
>      s->ass_ctx = ff_ass_split(avctx->subtitle_header);
> +
> +    // TODO: Initialize from ASS style record
> +    s->d.style_fontID   = DEFAULT_STYLE_FONT_ID;
> +    s->d.style_fontsize = DEFAULT_STYLE_FONTSIZE;
> +    s->d.style_color    = DEFAULT_STYLE_COLOR;
> +    s->d.style_flag     = DEFAULT_STYLE_FLAG;
> +
>      return s->ass_ctx ? 0 : AVERROR_INVALIDDATA;
>  }
>  
> @@ -270,6 +284,17 @@ static uint8_t mov_text_style_to_flag(const char
> style) return style_flag;
>  }
>  
> +static void mov_text_style_set(MovTextContext *s, uint8_t
> style_flags) +{
> +    if (!s->style_attributes_temp ||
> +        !((s->style_attributes_temp->style_flag & style_flags) ^
> style_flags)) {
> +        // setting flags that that are already set
> +        return;
> +    }
> +    if (mov_text_style_start(s))
> +        s->style_attributes_temp->style_flag |= style_flags;
> +}
> +
>  static void mov_text_style_cb(void *priv, const char style, int
> close) {
>      MovTextContext *s = priv;
> @@ -315,6 +340,19 @@ static void mov_text_end_cb(void *priv)
>      mov_text_style_start((MovTextContext*)priv);
>  }
>  
> +static void mov_text_dialog(MovTextContext *s, ASSDialog *dialog)
> +{
> +    ASSStyle * style = ff_ass_style_get(s->ass_ctx, dialog->style);
> +    uint8_t    style_flags;
> +
> +    if (style) {
> +        style_flags = (!!style->bold      * STYLE_FLAG_BOLD)   |
> +                      (!!style->italic    * STYLE_FLAG_ITALIC) |
> +                      (!!style->underline * STYLE_FLAG_UNDERLINE);
> +        mov_text_style_set(s, style_flags);
> +    }
> +}
> +
>  static uint16_t utf8_strlen(const char *text, int len)
>  {
>      uint16_t i = 0, ret = 0;
> @@ -386,6 +424,7 @@ static int mov_text_encode_frame(AVCodecContext
> *avctx, unsigned char *buf, int num;
>              dialog = ff_ass_split_dialog(s->ass_ctx, ass, 0, &num);
>              for (; dialog && num--; dialog++) {
> +                mov_text_dialog(s, dialog);
>                  ff_ass_split_override_codes(&mov_text_callbacks, s,
> dialog->text); }
>          } else {
> @@ -393,6 +432,7 @@ static int mov_text_encode_frame(AVCodecContext
> *avctx, unsigned char *buf, dialog = ff_ass_split_dialog2(s->ass_ctx,
> ass); if (!dialog)
>                  return AVERROR(ENOMEM);
> +            mov_text_dialog(s, dialog);
>              ff_ass_split_override_codes(&mov_text_callbacks, s,
> dialog->text); ff_ass_free_dialog(&dialog);
>  #if FF_API_ASS_TIMING

LGTM


--phil