[FFmpeg-devel] [PATCH v10] avcodec: add farbfeld encoder, decoder and demuxer

Lynne dev at lynne.ee
Fri Jun 7 23:58:59 EEST 2024


On 07/06/2024 22:22, Paul B Mahol wrote:
> On Fri, Jun 7, 2024 at 8:12 PM Lynne via ffmpeg-devel <
> ffmpeg-devel at ffmpeg.org> wrote:
> 
>> On 07/06/2024 19:47, Marcus B Spencer wrote:
>>> farbfeld is an uncompressed image format that is a part of suckless
>>> tools (https://tools.suckless.org).
>>>
>>> Its documentation is available at https://tools.suckless.org/farbfeld.
>>>
>>> Add support for this image format in avcodec and avformat, and update
>> the image2
>>> format accordingly.
>>>
>>> Signed-off-by: Marcus B Spencer <marcus at marcusspencer.xyz>
>>> ---
>>>    Changelog                 |  1 +
>>>    doc/general_contents.texi |  2 +
>>>    libavcodec/Makefile       |  2 +
>>>    libavcodec/allcodecs.c    |  2 +
>>>    libavcodec/codec_desc.c   |  7 +++
>>>    libavcodec/codec_id.h     |  1 +
>>>    libavcodec/farbfelddec.c  | 82 +++++++++++++++++++++++++++++++++
>>>    libavcodec/farbfeldenc.c  | 96 +++++++++++++++++++++++++++++++++++++++
>>>    libavcodec/version.h      |  4 +-
>>>    libavformat/Makefile      |  1 +
>>>    libavformat/allformats.c  |  1 +
>>>    libavformat/img2.c        |  1 +
>>>    libavformat/img2dec.c     | 16 +++++++
>>>    libavformat/img2enc.c     |  2 +-
>>>    libavformat/version.h     |  4 +-
>>>    15 files changed, 217 insertions(+), 5 deletions(-)
>>>    create mode 100644 libavcodec/farbfelddec.c
>>>    create mode 100644 libavcodec/farbfeldenc.c
>>>
>>> diff --git a/Changelog b/Changelog
>>> index 03d6b29ad8..102c718ffc 100644
>>> --- a/Changelog
>>> +++ b/Changelog
>>> @@ -12,6 +12,7 @@ version <next>:
>>>    - qsv_params option added for QSV encoders
>>>    - VVC decoder compatible with DVB test content
>>>    - xHE-AAC decoder
>>> +- farbfeld encoder, decoder and demuxer
>>>
>>>
>>>    version 7.0:
>>> diff --git a/doc/general_contents.texi b/doc/general_contents.texi
>>> index e7cf4f8239..fab30610a4 100644
>>> --- a/doc/general_contents.texi
>>> +++ b/doc/general_contents.texi
>>> @@ -853,6 +853,8 @@ following image formats are supported:
>>>        @tab X PixMap image format
>>>    @item XWD  @tab X @tab X
>>>        @tab X Window Dump image format
>>> + at item FF           @tab X @tab X
>>> +    @tab farbfeld uncompressed image format
>>>    @end multitable
>>>
>>>    @code{X} means that the feature in that column (encoding / decoding)
>> is supported.
>>> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
>>> index 8ab4398b6c..08a3d39af0 100644
>>> --- a/libavcodec/Makefile
>>> +++ b/libavcodec/Makefile
>>> @@ -356,6 +356,8 @@ OBJS-$(CONFIG_ESCAPE130_DECODER)       += escape130.o
>>>    OBJS-$(CONFIG_EVRC_DECODER)            += evrcdec.o acelp_vectors.o
>> lsp.o
>>>    OBJS-$(CONFIG_EXR_DECODER)             += exr.o exrdsp.o half2float.o
>>>    OBJS-$(CONFIG_EXR_ENCODER)             += exrenc.o float2half.o
>>> +OBJS-$(CONFIG_FARBFELD_DECODER)        += farbfelddec.o
>>> +OBJS-$(CONFIG_FARBFELD_ENCODER)        += farbfeldenc.o
>>>    OBJS-$(CONFIG_FASTAUDIO_DECODER)       += fastaudio.o
>>>    OBJS-$(CONFIG_FFV1_DECODER)            += ffv1dec.o ffv1.o
>>>    OBJS-$(CONFIG_FFV1_ENCODER)            += ffv1enc.o ffv1.o
>>> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
>>> index b102a8069e..9f9eda8ec6 100644
>>> --- a/libavcodec/allcodecs.c
>>> +++ b/libavcodec/allcodecs.c
>>> @@ -115,6 +115,8 @@ extern const FFCodec ff_escape124_decoder;
>>>    extern const FFCodec ff_escape130_decoder;
>>>    extern const FFCodec ff_exr_encoder;
>>>    extern const FFCodec ff_exr_decoder;
>>> +extern const FFCodec ff_farbfeld_decoder;
>>> +extern const FFCodec ff_farbfeld_encoder;
>>>    extern const FFCodec ff_ffv1_encoder;
>>>    extern const FFCodec ff_ffv1_decoder;
>>>    extern const FFCodec ff_ffvhuff_encoder;
>>> diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
>>> index a28ef68061..33dbd2ce94 100644
>>> --- a/libavcodec/codec_desc.c
>>> +++ b/libavcodec/codec_desc.c
>>> @@ -1959,6 +1959,13 @@ static const AVCodecDescriptor
>> codec_descriptors[] = {
>>>            .long_name = NULL_IF_CONFIG_SMALL("LEAD MCMP"),
>>>            .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
>>>        },
>>> +    {
>>> +        .id        = AV_CODEC_ID_FARBFELD,
>>> +        .type      = AVMEDIA_TYPE_VIDEO,
>>> +        .name      = "farbfeld",
>>> +        .long_name = NULL_IF_CONFIG_SMALL("farbfeld uncompressed
>> image"),
>>> +        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSLESS,
>>> +    },
>>>
>>>        /* various PCM "codecs" */
>>>        {
>>> diff --git a/libavcodec/codec_id.h b/libavcodec/codec_id.h
>>> index 0ab1e34a61..d4b0d23f7e 100644
>>> --- a/libavcodec/codec_id.h
>>> +++ b/libavcodec/codec_id.h
>>> @@ -322,6 +322,7 @@ enum AVCodecID {
>>>        AV_CODEC_ID_RTV1,
>>>        AV_CODEC_ID_VMIX,
>>>        AV_CODEC_ID_LEAD,
>>> +    AV_CODEC_ID_FARBFELD,
>>>
>>>        /* various PCM "codecs" */
>>>        AV_CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at
>> the start of audio codecs
>>> diff --git a/libavcodec/farbfelddec.c b/libavcodec/farbfelddec.c
>>> new file mode 100644
>>> index 0000000000..b56727225c
>>> --- /dev/null
>>> +++ b/libavcodec/farbfelddec.c
>>> @@ -0,0 +1,82 @@
>>> +/*
>>> + * Copyright (c) 2024 Marcus B Spencer <marcus at marcusspencer.xyz>
>>> + *
>>> + * Permission is hereby granted, free of charge, to any person
>> obtaining a copy
>>> + * of this software and associated documentation files (the
>> “Software”), to
>>> + * deal in the Software without restriction, including without
>> limitation the
>>> + * rights to use, copy, modify, merge, publish, distribute, sublicense,
>> and/or
>>> + * sell copies of the Software, and to permit persons to whom the
>> Software is
>>> + * furnished to do so, subject to the following conditions:
>>> + *
>>> + * The above copyright notice and this permission notice shall be
>> included in
>>> + * all copies or substantial portions of the Software.
>>> + *
>>> + * THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND,
>> EXPRESS OR
>>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
>> MERCHANTABILITY,
>>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
>> SHALL THE
>>> + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
>> OTHER
>>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
>> ARISING
>>> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
>> DEALINGS
>>> + * IN THE SOFTWARE.
>>> + */
>>> +
>>> +#include "avcodec.h"
>>> +#include "bytestream.h"
>>> +#include "codec_internal.h"
>>> +#include "decode.h"
>>> +#include "libavutil/imgutils.h"
>>> +#include "thread.h"
>>> +
>>> +static int farbfeld_decode_frame(AVCodecContext *ctx, AVFrame *p,
>>> +                                 int *got_frame, AVPacket *pkt)
>>> +{
>>> +    int width, height;
>>> +    GetByteContext g;
>>> +    int ret;
>>> +
>>> +    bytestream2_init(&g, pkt->data, pkt->size);
>>> +    bytestream2_skip(&g, 8);
>>> +
>>> +    width  = bytestream2_get_be32(&g);
>>> +    height = bytestream2_get_be32(&g);
>>> +
>>> +    if ((ret = ff_set_dimensions(ctx, width, height)) < 0)
>>> +        return ret;
>>> +
>>> +    ctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
>>> +
>>> +    if (ctx->skip_frame >= AVDISCARD_ALL)
>>> +        return pkt->size;
>>> +
>>> +    if ((ret = ff_thread_get_buffer(ctx, p, 0)) < 0)
>>> +        return ret;
>>> +
>>> +    if ((ret = av_image_get_buffer_size(ctx->pix_fmt, width, height,
>> 1)) < 0)
>>> +        return ret;
>>> +
>>> +    if (bytestream2_get_bytes_left(&g) < ret)
>>> +        return AVERROR_INVALIDDATA;
>>> +
>>> +    av_image_fill_arrays(
>>> +        p->data,
>>> +        p->linesize,
>>> +        g.buffer,
>>> +        ctx->pix_fmt,
>>> +        width,
>>> +        height,
>>> +        1
>>> +    );
>>> +
>>> +    *got_frame = 1;
>>> +
>>> +    return pkt->size;
>>> +}
>>> +
>>> +const FFCodec ff_farbfeld_decoder = {
>>> +    .p.name         = "farbfeld",
>>> +    CODEC_LONG_NAME("farbfeld uncompressed image"),
>>> +    .p.type         = AVMEDIA_TYPE_VIDEO,
>>> +    .p.id           = AV_CODEC_ID_FARBFELD,
>>> +    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
>>> +    FF_CODEC_DECODE_CB(farbfeld_decode_frame),
>>> +};
>>> diff --git a/libavcodec/farbfeldenc.c b/libavcodec/farbfeldenc.c
>>> new file mode 100644
>>> index 0000000000..2801324852
>>> --- /dev/null
>>> +++ b/libavcodec/farbfeldenc.c
>>> @@ -0,0 +1,96 @@
>>> +/*
>>> + * Copyright (c) 2024 Marcus B Spencer <marcus at marcusspencer.xyz>
>>> + *
>>> + * Permission is hereby granted, free of charge, to any person
>> obtaining a copy
>>> + * of this software and associated documentation files (the
>> “Software”), to
>>> + * deal in the Software without restriction, including without
>> limitation the
>>> + * rights to use, copy, modify, merge, publish, distribute, sublicense,
>> and/or
>>> + * sell copies of the Software, and to permit persons to whom the
>> Software is
>>> + * furnished to do so, subject to the following conditions:
>>> + *
>>> + * The above copyright notice and this permission notice shall be
>> included in
>>> + * all copies or substantial portions of the Software.
>>> + *
>>> + * THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND,
>> EXPRESS OR
>>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
>> MERCHANTABILITY,
>>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
>> SHALL THE
>>> + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
>> OTHER
>>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
>> ARISING
>>> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
>> DEALINGS
>>> + * IN THE SOFTWARE.
>>> + */
>>> +
>>> +#include "avcodec.h"
>>> +#include "bytestream.h"
>>> +#include "codec_internal.h"
>>> +#include "encode.h"
>>> +#include "libavutil/imgutils.h"
>>> +
>>> +#define HEADER_SIZE 16
>>> +#define PLANE_COUNT 4 // required by av_image_copy_to_buffer
>>> +
>>> +static int farbfeld_encode_frame(AVCodecContext *ctx, AVPacket *pkt,
>>> +                                 const AVFrame *p, int *got_packet)
>>> +{
>>> +    int raw_img_size = av_image_get_buffer_size(
>>> +        p->format,
>>> +        p->width,
>>> +        p->height,
>>> +        1
>>> +    );
>>> +    const uint8_t *planes[4];
>>> +    int64_t buf_size;
>>> +    uint8_t *buf;
>>> +    int ret;
>>> +
>>> +    if (raw_img_size < 0)
>>> +        return raw_img_size;
>>> +
>>> +#if INT_MAX > INT64_MAX - HEADER_SIZE
>>> +    if (raw_img_size > INT64_MAX - HEADER_SIZE)
>>> +        return AVERROR(ERANGE);
>>> +#endif
>>> +
>>> +    buf_size = (int64_t)raw_img_size + HEADER_SIZE;
>>> +
>>> +    if ((ret = ff_get_encode_buffer(ctx, pkt, buf_size, 0)) < 0)
>>> +        return ret;
>>> +
>>> +    buf = pkt->data;
>>> +
>>> +    bytestream_put_buffer(&buf, "farbfeld", 8);
>>> +
>>> +    bytestream_put_be32(&buf, ctx->width);
>>> +    bytestream_put_be32(&buf, ctx->height);
>>> +
>>> +    for (int i = 0; i < PLANE_COUNT; ++i)
>>> +        planes[i] = p->data[i];
>>> +
>>> +    av_image_copy_to_buffer(
>>> +        buf,
>>> +        raw_img_size,
>>> +        planes,
>>> +        p->linesize,
>>> +        p->format,
>>> +        p->width,
>>> +        p->height,
>>> +        1
>>> +    );
>>> +
>>> +    *got_packet = 1;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +const FFCodec ff_farbfeld_encoder = {
>>> +    .p.name         = "farbfeld",
>>> +    CODEC_LONG_NAME("farbfeld uncompressed image"),
>>> +    .p.type         = AVMEDIA_TYPE_VIDEO,
>>> +    .p.id           = AV_CODEC_ID_FARBFELD,
>>> +    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
>>> +    FF_CODEC_ENCODE_CB(farbfeld_encode_frame),
>>> +    .p.pix_fmts     = (const enum AVPixelFormat[]){
>>> +        AV_PIX_FMT_RGBA64BE,
>>> +        AV_PIX_FMT_NONE
>>> +    },
>>> +};
>>> diff --git a/libavcodec/version.h b/libavcodec/version.h
>>> index 39dbec0208..7acb261bb3 100644
>>> --- a/libavcodec/version.h
>>> +++ b/libavcodec/version.h
>>> @@ -29,8 +29,8 @@
>>>
>>>    #include "version_major.h"
>>>
>>> -#define LIBAVCODEC_VERSION_MINOR   6
>>> -#define LIBAVCODEC_VERSION_MICRO 101
>>> +#define LIBAVCODEC_VERSION_MINOR   7
>>> +#define LIBAVCODEC_VERSION_MICRO 100
>>>
>>>    #define LIBAVCODEC_VERSION_INT
>> AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
>>>
>> LIBAVCODEC_VERSION_MINOR, \
>>> diff --git a/libavformat/Makefile b/libavformat/Makefile
>>> index 1c4d9deccd..588a097149 100644
>>> --- a/libavformat/Makefile
>>> +++ b/libavformat/Makefile
>>> @@ -284,6 +284,7 @@ OBJS-$(CONFIG_IMAGE_CRI_PIPE_DEMUXER)     +=
>> img2dec.o img2.o
>>>    OBJS-$(CONFIG_IMAGE_DDS_PIPE_DEMUXER)     += img2dec.o img2.o
>>>    OBJS-$(CONFIG_IMAGE_DPX_PIPE_DEMUXER)     += img2dec.o img2.o
>>>    OBJS-$(CONFIG_IMAGE_EXR_PIPE_DEMUXER)     += img2dec.o img2.o
>>> +OBJS-$(CONFIG_IMAGE_FARBFELD_PIPE_DEMUXER)+= img2dec.o img2.o
>>>    OBJS-$(CONFIG_IMAGE_GEM_PIPE_DEMUXER)     += img2dec.o img2.o
>>>    OBJS-$(CONFIG_IMAGE_GIF_PIPE_DEMUXER)     += img2dec.o img2.o
>>>    OBJS-$(CONFIG_IMAGE_HDR_PIPE_DEMUXER)     += img2dec.o img2.o
>>> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
>>> index 305fa46532..6900ee8199 100644
>>> --- a/libavformat/allformats.c
>>> +++ b/libavformat/allformats.c
>>> @@ -537,6 +537,7 @@ extern const FFInputFormat
>> ff_image_cri_pipe_demuxer;
>>>    extern const FFInputFormat  ff_image_dds_pipe_demuxer;
>>>    extern const FFInputFormat  ff_image_dpx_pipe_demuxer;
>>>    extern const FFInputFormat  ff_image_exr_pipe_demuxer;
>>> +extern const FFInputFormat  ff_image_farbfeld_pipe_demuxer;
>>>    extern const FFInputFormat  ff_image_gem_pipe_demuxer;
>>>    extern const FFInputFormat  ff_image_gif_pipe_demuxer;
>>>    extern const FFInputFormat  ff_image_hdr_pipe_demuxer;
>>> diff --git a/libavformat/img2.c b/libavformat/img2.c
>>> index 9981867f82..77edc7ff9b 100644
>>> --- a/libavformat/img2.c
>>> +++ b/libavformat/img2.c
>>> @@ -95,6 +95,7 @@
>>>        TAG(QOI,             qoi      ) \
>>>        TAG(RADIANCE_HDR,    hdr      ) \
>>>        TAG(WBMP,            wbmp     ) \
>>> +    TAG(FARBFELD,        ff       ) \
>>>        TAG(NONE,                     )
>>>
>>>    #define LENGTH_CHECK(CODECID, STR) \
>>> diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
>>> index a40675d434..70091c70f2 100644
>>> --- a/libavformat/img2dec.c
>>> +++ b/libavformat/img2dec.c
>>> @@ -1205,6 +1205,21 @@ static int vbn_probe(const AVProbeData *p)
>>>        return 0;
>>>    }
>>>
>>> +static int farbfeld_probe(const AVProbeData *p)
>>> +{
>>> +    if (p->buf_size < 16)
>>> +        return 0;
>>> +
>>> +    if (memcmp(p->buf, "farbfeld", 8))
>>> +        return 0;
>>> +
>>> +    // check if width or height is zero
>>> +    if (AV_RB32(p->buf + 8) == 0 || AV_RB32(p->buf + 12) == 0)
>>> +        return 0;
>>> +
>>> +    return AVPROBE_SCORE_MAX - 1;
>>> +}
>>> +
>>>    #define IMAGEAUTO_DEMUXER_0(imgname, codecid)
>>>    #define IMAGEAUTO_DEMUXER_1(imgname, codecid)\
>>>    const FFInputFormat ff_image_ ## imgname ## _pipe_demuxer = {\
>>> @@ -1234,6 +1249,7 @@ IMAGEAUTO_DEMUXER(cri,       CRI)
>>>    IMAGEAUTO_DEMUXER(dds,       DDS)
>>>    IMAGEAUTO_DEMUXER(dpx,       DPX)
>>>    IMAGEAUTO_DEMUXER(exr,       EXR)
>>> +IMAGEAUTO_DEMUXER(farbfeld,  FARBFELD)
>>>    IMAGEAUTO_DEMUXER(gem,       GEM)
>>>    IMAGEAUTO_DEMUXER(gif,       GIF)
>>>    IMAGEAUTO_DEMUXER_EXT(hdr,   RADIANCE_HDR, HDR)
>>> diff --git a/libavformat/img2enc.c b/libavformat/img2enc.c
>>> index 526a11e5ee..13355a6fad 100644
>>> --- a/libavformat/img2enc.c
>>> +++ b/libavformat/img2enc.c
>>> @@ -276,7 +276,7 @@ const FFOutputFormat ff_image2_muxer = {
>>>        .p.long_name    = NULL_IF_CONFIG_SMALL("image2 sequence"),
>>>        .p.extensions   =
>> "bmp,dpx,exr,jls,jpeg,jpg,jxl,ljpg,pam,pbm,pcx,pfm,pgm,pgmyuv,phm,"
>>>
>>   "png,ppm,sgi,tga,tif,tiff,jp2,j2c,j2k,xwd,sun,ras,rs,im1,im8,"
>>> -
>> "im24,sunras,vbn,xbm,xface,pix,y,avif,qoi,hdr,wbmp",
>>> +
>> "im24,sunras,vbn,xbm,xface,pix,y,avif,qoi,hdr,wbmp,ff",
>>>        .priv_data_size = sizeof(VideoMuxData),
>>>        .p.video_codec  = AV_CODEC_ID_MJPEG,
>>>        .write_header   = write_header,
>>> diff --git a/libavformat/version.h b/libavformat/version.h
>>> index 4687cd857c..af7d0a1024 100644
>>> --- a/libavformat/version.h
>>> +++ b/libavformat/version.h
>>> @@ -31,8 +31,8 @@
>>>
>>>    #include "version_major.h"
>>>
>>> -#define LIBAVFORMAT_VERSION_MINOR   3
>>> -#define LIBAVFORMAT_VERSION_MICRO 104
>>> +#define LIBAVFORMAT_VERSION_MINOR   4
>>> +#define LIBAVFORMAT_VERSION_MICRO 100
>>>
>>>    #define LIBAVFORMAT_VERSION_INT
>> AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
>>>
>> LIBAVFORMAT_VERSION_MINOR, \
>>
>> Since the "codec" is essentially just raw data, you should just make the
>> demuxer output native RGBA64, and the muxer accept RGBA64. There's no
>> reason to have this as a codec, since the header field is completely
>> redundant with the fields an AVFrame contains.
>>
>> Plus, you avoid all copies entirely in this way.
>>
> 
> But each single frame have header and dimensions in it.
> Also pipe demuxer will need parser, its trivial to write one for this
> format.

Nothing here requires a codec. Wrapped aframes have a dimension on a 
per-frame basis, and the lavf framework can deal with piping as each 
frame carries identification.
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