From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTPS id 6C5EE4B7A2 for ; Sat, 1 Mar 2025 14:30:03 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 5CBB268E133; Sat, 1 Mar 2025 16:29:49 +0200 (EET) Received: from smtp.waider.ie (smtp.waider.ie [52.31.250.228]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 6181168E0F8 for ; Sat, 1 Mar 2025 16:29:42 +0200 (EET) Received: from smtpclient.apple (unknown [109.255.224.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.waider.ie (Postfix) with ESMTPSA id 6951E49C8F for ; Sat, 1 Mar 2025 14:29:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=waider.ie; s=waider_ie; t=1740839381; bh=6PvJQTzBSaWjaL+2pjGcoLH50Z6xOdJR68Rg8dHuW1A=; h=Content-Type:Mime-Version:Subject:To:From:In-Reply-To:Date: Content-Transfer-Encoding:Message-Id:References; b=Sa6IN8zU/Juh4f4ULxtAtNpmwxuaOiXnJs4hoUMF8D0LGehzdoG9Q6+vdzroixzTc 9SJDB0xTN18jGwvI1Hd9jq5vN7XigzInSLR3/0hZXD3N3DX2ALn3RWllMTPAOL5GrH aGiKUy2ZMoR2258+oFslEab+xgy88ND5Y18EHizc= Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3826.400.131.1.6\)) To: ffmpeg-devel@ffmpeg.org From: Ronan Waide In-Reply-To: Date: Sat, 1 Mar 2025 14:29:34 +0000 Message-Id: <5B5E99C1-EE70-47B7-B3BF-DEE19C41DBC7@waider.ie> References: Organization: Poor, at best X-Mailer: Apple Mail (2.3826.400.131.1.6) X-Spam-Status: No, score=-102.9 required=5.0 tests=ALL_TRUSTED,BAYES_00, URIBL_BLOCKED,URIBL_DBL_BLOCKED_OPENDNS,URIBL_ZEN_BLOCKED_OPENDNS, USER_IN_WELCOMELIST,USER_IN_WHITELIST autolearn=ham autolearn_force=no version=3.4.3 X-Spam-Checker-Version: SpamAssassin 3.4.3 (2019-12-06) on ec2.waider.ie Subject: Re: [FFmpeg-devel] [PATCH v3] libavcodec/dvbsubenc.c: add a disable_2bpp option to work around some decoders. X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: > On 1 Mar 2025, at 14:10, Ronan Waide wrote: > > (changes from previous attempt: fixed an error in the docfile and made sure I'm diffing against origin/master) > > As noted in the code in several places, some DVB subtitle decoders > don't handle 2bpp color. This patch adds a disable_2bpp option which > disables the 2bpp format; subtitles which would use 2bpp will be bumped > up to 4bpp. > > Signed-off-by: Ronan Waide > --- > doc/encoders.texi | 27 ++++++++++++++ > libavcodec/dvbsubenc.c | 85 +++++++++++++++++++++++++++++++++--------- > 2 files changed, 95 insertions(+), 17 deletions(-) > > diff --git a/doc/encoders.texi b/doc/encoders.texi > index f3fcc1aa60..07984b6b54 100644 > --- a/doc/encoders.texi > +++ b/doc/encoders.texi > @@ -4484,6 +4484,33 @@ Reduces detail but attempts to preserve color at extremely low bitrates. > @chapter Subtitles Encoders > @c man begin SUBTITLES ENCODERS > > +@section dvbsub > + > +This codec encodes the bitmap subtitle format that is used in DVB > +broadcasts and recordings. The bitmaps are typically embedded in a > +container such as MPEG-TS as a separate stream. > + > +@subsection Options > + > +@table @option > +@item disable_2bpp @var{boolean} > +Disable the 2 bits-per-pixel encoding format. > + > +DVB supports 2, 4, and 8 bits-per-pixel color lookup tables. However, > +not all players support or properly support 2 bits-per-pixel, > +resulting in unusable subtitles. > +@table @option > +@item 0 > +The 2 bits-per-pixel encoding format will be used for subtitles with 4 > +colors or less. (default) > + > +@item 1 > +The 2 bits-per-pixel encoding format will be disabled, and subtitles > +with 4 colors or less will use a 4 bits-per-pixel format. > +@end table > + > +@end table > + > @section dvdsub > > This codec encodes the bitmap subtitle format that is used in DVDs. > diff --git a/libavcodec/dvbsubenc.c b/libavcodec/dvbsubenc.c > index 822e3a5309..727a75e901 100644 > --- a/libavcodec/dvbsubenc.c > +++ b/libavcodec/dvbsubenc.c > @@ -22,9 +22,13 @@ > #include "bytestream.h" > #include "codec_internal.h" > #include "libavutil/colorspace.h" > +#include "libavutil/opt.h" > > typedef struct DVBSubtitleContext { > + AVClass * class; > int object_version; > + int disable_2bpp; > + int min_colors; > } DVBSubtitleContext; > > #define PUTBITS2(val)\ > @@ -38,6 +42,18 @@ typedef struct DVBSubtitleContext { > }\ > } > > +static int dvbsub_init(AVCodecContext *avctx) > +{ > + DVBSubtitleContext *s = avctx->priv_data; > + if (s->disable_2bpp) { > + av_log(avctx, AV_LOG_DEBUG, "Disabling 2bpp subtitles.\n"); > + s->min_colors = 16; > + } else { > + s->min_colors = 0; > + } > + return 0; > +} > + > static int dvb_encode_rle2(uint8_t **pq, int buf_size, > const uint8_t *bitmap, int linesize, > int w, int h) > @@ -326,18 +342,22 @@ static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size, > > if (h->num_rects) { > for (clut_id = 0; clut_id < h->num_rects; clut_id++) { > - if (buf_size < 6 + h->rects[clut_id]->nb_colors * 6) > + int nb_colors = s->min_colors > h->rects[clut_id]->nb_colors > + ? s->min_colors > + : h->rects[clut_id]->nb_colors; > + > + if (buf_size < 6 + nb_colors * 6) > return AVERROR_BUFFER_TOO_SMALL; > > /* CLUT segment */ > > - if (h->rects[clut_id]->nb_colors <= 4) { > + if (nb_colors <= 4) { > /* 2 bpp, some decoders do not support it correctly */ > bpp_index = 0; > - } else if (h->rects[clut_id]->nb_colors <= 16) { > + } else if (nb_colors <= 16) { > /* 4 bpp, standard encoding */ > bpp_index = 1; > - } else if (h->rects[clut_id]->nb_colors <= 256) { > + } else if (nb_colors <= 256) { > /* 8 bpp, standard encoding */ > bpp_index = 2; > } else { > @@ -354,16 +374,24 @@ static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size, > *q++ = clut_id; > *q++ = (0 << 4) | 0xf; /* version = 0 */ > > - for(i = 0; i < h->rects[clut_id]->nb_colors; i++) { > + for(i = 0; i < nb_colors; i++) { > *q++ = i; /* clut_entry_id */ > *q++ = (1 << (7 - bpp_index)) | (0xf << 1) | 1; /* 2 bits/pixel full range */ > { > int a, r, g, b; > - uint32_t x= ((uint32_t*)h->rects[clut_id]->data[1])[i]; > - a = (x >> 24) & 0xff; > - r = (x >> 16) & 0xff; > - g = (x >> 8) & 0xff; > - b = (x >> 0) & 0xff; > + if (i < h->rects[clut_id]->nb_colors) { > + uint32_t x= ((uint32_t*)h->rects[clut_id]->data[1])[i]; > + a = (x >> 24) & 0xff; > + r = (x >> 16) & 0xff; > + g = (x >> 8) & 0xff; > + b = (x >> 0) & 0xff; > + } else { > + /* pad out the CLUT */ > + a = 0; > + r = 0; > + g = 0; > + b = 0; > + } > > *q++ = RGB_TO_Y_CCIR(r, g, b); > *q++ = RGB_TO_V_CCIR(r, g, b, 0); > @@ -373,7 +401,7 @@ static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size, > } > > bytestream_put_be16(&pseg_len, q - pseg_len - 2); > - buf_size -= 6 + h->rects[clut_id]->nb_colors * 6; > + buf_size -= 6 + nb_colors * 6; > } > > if (buf_size < h->num_rects * 22) > @@ -381,14 +409,17 @@ static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size, > for (region_id = 0; region_id < h->num_rects; region_id++) { > > /* region composition segment */ > + int nb_colors = s->min_colors > h->rects[region_id]->nb_colors > + ? s->min_colors > + : h->rects[region_id]->nb_colors; > > - if (h->rects[region_id]->nb_colors <= 4) { > + if (nb_colors <= 4) { > /* 2 bpp, some decoders do not support it correctly */ > bpp_index = 0; > - } else if (h->rects[region_id]->nb_colors <= 16) { > + } else if (nb_colors <= 16) { > /* 4 bpp, standard encoding */ > bpp_index = 1; > - } else if (h->rects[region_id]->nb_colors <= 256) { > + } else if (nb_colors <= 256) { > /* 8 bpp, standard encoding */ > bpp_index = 2; > } else { > @@ -424,17 +455,21 @@ static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size, > const uint8_t *bitmap, int linesize, > int w, int h); > > + int nb_colors = s->min_colors > h->rects[object_id]->nb_colors > + ? s->min_colors > + : h->rects[object_id]->nb_colors; > + > if (buf_size < 13) > return AVERROR_BUFFER_TOO_SMALL; > > /* bpp_index maths */ > - if (h->rects[object_id]->nb_colors <= 4) { > + if (nb_colors <= 4) { > /* 2 bpp, some decoders do not support it correctly */ > dvb_encode_rle = dvb_encode_rle2; > - } else if (h->rects[object_id]->nb_colors <= 16) { > + } else if (nb_colors <= 16) { > /* 4 bpp, standard encoding */ > dvb_encode_rle = dvb_encode_rle4; > - } else if (h->rects[object_id]->nb_colors <= 256) { > + } else if (nb_colors <= 256) { > /* 8 bpp, standard encoding */ > dvb_encode_rle = dvb_encode_rle8; > } else { > @@ -506,6 +541,20 @@ static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size, > return q - outbuf; > } > > +#define OFFSET(x) offsetof(DVBSubtitleContext, x) > +#define SE AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_ENCODING_PARAM > +static const AVOption options[] = { > + {"disable_2bpp", "disable the 2bpp subtitle encoder", OFFSET(disable_2bpp), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, SE}, > + { NULL }, > +}; > + > +static const AVClass dvbsubenc_class = { > + .class_name = "DVBSUB subtitle encoder", > + .item_name = av_default_item_name, > + .option = options, > + .version = LIBAVUTIL_VERSION_INT, > +}; > + > const FFCodec ff_dvbsub_encoder = { > .p.name = "dvbsub", > CODEC_LONG_NAME("DVB subtitles"), > @@ -513,4 +562,6 @@ const FFCodec ff_dvbsub_encoder = { > .p.id = AV_CODEC_ID_DVB_SUBTITLE, > .priv_data_size = sizeof(DVBSubtitleContext), > FF_CODEC_ENCODE_SUB_CB(dvbsub_encode), > + .init = dvbsub_init, > + .p.priv_class = &dvbsubenc_class, > }; > -- > 2.39.5 (Apple Git-154) > This failed again, and I see the problem - I'm diffing against https://github.com/FFmpeg/FFmpeg.git rather than https://git.ffmpeg.org/ffmpeg.git. Apologies for the confusion on my part. Fixed fix of a fix incoming... Cheers, Waider. -- Ronan Waide waider@waider.ie _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".