[FFmpeg-devel] [PATCH 2/4] Silicon Graphics Motion Video Compressor 1 & 2 decoder

Paul B Mahol onemda at gmail.com
Tue Dec 11 12:14:09 CET 2012


On 12/11/12, Peter Ross <pross at xvid.org> wrote:
> Signed-off-by: Peter Ross <pross at xvid.org>
> ---
>  Changelog               |   1 +
>  doc/general.texi        |   2 +
>  libavcodec/Makefile     |   2 +
>  libavcodec/allcodecs.c  |   2 +
>  libavcodec/avcodec.h    |   2 +
>  libavcodec/codec_desc.c |  14 +++
>  libavcodec/mvcdec.c     | 284
> ++++++++++++++++++++++++++++++++++++++++++++++++
>  7 files changed, 307 insertions(+)
>  create mode 100644 libavcodec/mvcdec.c
>
> diff --git a/Changelog b/Changelog
> index e8e6911..93f34e3 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -41,6 +41,7 @@ version <next>:
>  - VobSub demuxer
>  - JSON captions for TED talks decoding support
>  - SGI RLE 8-bit decoder
> +- Silicon Graphics Motion Video Compressor 1 & 2 decoder
>
>
>  version 1.0:
> diff --git a/doc/general.texi b/doc/general.texi
> index eb12364..22988b2 100644
> --- a/doc/general.texi
> +++ b/doc/general.texi
> @@ -667,6 +667,8 @@ following image formats are supported:
>  @item SGI RLE 8-bit          @tab     @tab  X
>  @item Sierra VMD video       @tab     @tab  X
>      @tab Used in Sierra VMD files.
> + at item Silicon Graphics Motion Video Compressor 1 (MVC1)  @tab     @tab  X
> + at item Silicon Graphics Motion Video Compressor 2 (MVC2)  @tab     @tab  X
>  @item Smacker video          @tab     @tab  X
>      @tab Video encoding used in Smacker.
>  @item SMPTE VC-1             @tab     @tab  X
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index 9e6edc1..087417b 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -310,6 +310,8 @@ OBJS-$(CONFIG_MSVIDEO1_DECODER)        += msvideo1.o
>  OBJS-$(CONFIG_MSVIDEO1_ENCODER)        += msvideo1enc.o elbg.o
>  OBJS-$(CONFIG_MSZH_DECODER)            += lcldec.o
>  OBJS-$(CONFIG_MTS2_DECODER)            += mss4.o mss34dsp.o
> +OBJS-$(CONFIG_MVC1_DECODER)            += mvcdec.o
> +OBJS-$(CONFIG_MVC2_DECODER)            += mvcdec.o
>  OBJS-$(CONFIG_MXPEG_DECODER)           += mxpegdec.o mjpegdec.o mjpeg.o
>  OBJS-$(CONFIG_NELLYMOSER_DECODER)      += nellymoserdec.o nellymoser.o
>  OBJS-$(CONFIG_NELLYMOSER_ENCODER)      += nellymoserenc.o nellymoser.o \
> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
> index 5dcd509..edeb3fb 100644
> --- a/libavcodec/allcodecs.c
> +++ b/libavcodec/allcodecs.c
> @@ -183,6 +183,8 @@ void avcodec_register_all(void)
>      REGISTER_ENCDEC  (MSVIDEO1, msvideo1);
>      REGISTER_DECODER (MSZH, mszh);
>      REGISTER_DECODER (MTS2, mts2);
> +    REGISTER_DECODER (MVC1, mvc1);
> +    REGISTER_DECODER (MVC2, mvc2);
>      REGISTER_DECODER (MXPEG, mxpeg);
>      REGISTER_DECODER (NUV, nuv);
>      REGISTER_DECODER (PAF_VIDEO, paf_video);
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index b9317f0..47b0869 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -286,6 +286,8 @@ enum AVCodecID {
>      AV_CODEC_ID_CPIA       = MKBETAG('C','P','I','A'),
>      AV_CODEC_ID_XFACE      = MKBETAG('X','F','A','C'),
>      AV_CODEC_ID_SGIRLE     = MKBETAG('S','G','I','R'),
> +    AV_CODEC_ID_MVC1       = MKBETAG('M','V','C','1'),
> +    AV_CODEC_ID_MVC2       = MKBETAG('M','V','C','2'),
>
>      /* various PCM "codecs" */
>      AV_CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at the
> start of audio codecs
> diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
> index 4ba31e9..de61d0e 100644
> --- a/libavcodec/codec_desc.c
> +++ b/libavcodec/codec_desc.c
> @@ -1066,6 +1066,20 @@ static const AVCodecDescriptor codec_descriptors[] =
> {
>          .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSLESS,
>      },
>      {
> +        .id        = AV_CODEC_ID_MVC1,
> +        .type      = AVMEDIA_TYPE_VIDEO,
> +        .name      = "mvc1",
> +        .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video
> Compressor 1"),
> +        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
> +    },
> +    {
> +        .id        = AV_CODEC_ID_MVC2,
> +        .type      = AVMEDIA_TYPE_VIDEO,
> +        .name      = "mvc2",
> +        .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video
> Compressor 2"),
> +        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSY,
> +    },
> +    {
>          .id        = AV_CODEC_ID_MXPEG,
>          .type      = AVMEDIA_TYPE_VIDEO,
>          .name      = "mxpeg",
> diff --git a/libavcodec/mvcdec.c b/libavcodec/mvcdec.c
> new file mode 100644
> index 0000000..43d660a
> --- /dev/null
> +++ b/libavcodec/mvcdec.c
> @@ -0,0 +1,284 @@
> +/*
> + * Silicon Graphics Motion Video Compressor 1 & 2 decoder
> + * Copyright (c) 2012 Peter Ross
> + *
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * FFmpeg is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
> USA
> + */
> +
> +/**
> + * @file
> + * Silicon Graphics Motion Video Compressor 1 & 2 decoder
> + */
> +
> +#include "libavutil/intreadwrite.h"
> +#include "avcodec.h"
> +#include "bytestream.h"
> +
> +typedef struct MvcContext {
> +    AVFrame frame;
> +    int vflip;
> +} MvcContext;
> +
> +static av_cold int mvc_decode_init(AVCodecContext *avctx)
> +{
> +    MvcContext *s = avctx->priv_data;
> +    int width  = avctx->width;
> +    int height = avctx->height;
> +
> +    if (avctx->codec_id == AV_CODEC_ID_MVC1) {
> +        width  += 3;
> +        height += 3;
> +    }
> +    width  &= ~3;
> +    height &= ~3;
> +    if (width != avctx->width || height != avctx->height)
> +        avcodec_set_dimensions(avctx, width, height);
> +
> +    avctx->pix_fmt = (avctx->codec_id == AV_CODEC_ID_MVC1) ?
> AV_PIX_FMT_RGB555 : AV_PIX_FMT_BGRA;
> +    avcodec_get_frame_defaults(&s->frame);
> +    s->frame.data[0] = NULL;

??? Same question as for sgirle.
> +
> +    s->vflip = avctx->extradata_size >= 9 && !memcmp(avctx->extradata +
> avctx->extradata_size - 9, "BottomUp", 9);
> +    return 0;
> +}
> +
> +static void decode_mvc1(AVCodecContext *avctx, GetByteContext *gb, uint8_t
> *dst_start, int width, int height, int linesize)
> +{
> +    uint8_t *dst;
> +    uint16_t v[8];
> +    int mask, x, y, i;
> +
> +    x = y= 0;
> +    while (bytestream2_get_bytes_left(gb) >= 6) {
> +        mask = bytestream2_get_be16u(gb);
> +        v[0] = bytestream2_get_be16u(gb);
> +        v[1] = bytestream2_get_be16u(gb);
> +        if ((v[0] & 0x8000)) {
> +            if (bytestream2_get_bytes_left(gb) < 12) {
> +                av_log(avctx, AV_LOG_WARNING, "buffer overflow\n");
> +                return;
> +            }
> +            for (i = 2; i < 8; i++)
> +                v[i] = bytestream2_get_be16u(gb);
> +        } else {
> +            v[2] = v[4] = v[6] = v[0];
> +            v[3] = v[5] = v[7] = v[1];
> +        }
> +
> +#define PIX16(target, true, false) \
> +        i = (mask & target) ? true : false; \
> +        AV_WN16A(dst, (v[i] & 0x7C00) | (v[i] & 0x3E0) | (v[i] & 0x1F)); \
> +        dst += 2;
> +
> +#define ROW16(row, a1, a0, b1, b0) \
> +        dst = dst_start + (y + row) * linesize + x * 2; \
> +        PIX16(1 << (row * 4),     a1, a0) \
> +        PIX16(1 << (row * 4 + 1), a1, a0) \
> +        PIX16(1 << (row * 4 + 2), b1, b0) \
> +        PIX16(1 << (row * 4 + 3), b1, b0)
> +
> +        ROW16(0, 0, 1, 2, 3);
> +        ROW16(1, 0, 1, 2, 3);
> +        ROW16(2, 4, 5, 6, 7);
> +        ROW16(3, 4, 5, 6, 7);
> +
> +        x += 4;
> +        if (x >= width) {
> +            y += 4;
> +            if (y >= height) {
> +                break;
> +            }
> +            x = 0;
> +        }
> +    }
> +}
> +
> +static void set_4x4_block(uint8_t *dst, int linesize, uint32_t pixel)
> +{
> +    int i, j;
> +    for (j = 0; j < 4; j++)
> +        for (i = 0; i < 4; i++)
> +            AV_WN32A(dst + j * linesize + i * 4, pixel);
> +}

Something similar is in dsputil, please use that.

> +
> +#define PIX32(target, true, false) \
> +    AV_WN32A(dst, (mask & target) ? v[true] : v[false]); \
> +    dst += 4;
> +
> +#define ROW32(row, a1, a0, b1, b0) \
> +    dst = dst_start + (y + row) * linesize + x * 4; \
> +    PIX32(1 << (row * 4),     a1, a0) \
> +    PIX32(1 << (row * 4 + 1), a1, a0) \
> +    PIX32(1 << (row * 4 + 2), b1, b0) \
> +    PIX32(1 << (row * 4 + 3), b1, b0)
> +
> +#define MVC2_BLOCK \
> +    ROW32(0, 1, 0, 3, 2); \
> +    ROW32(1, 1, 0, 3, 2); \
> +    ROW32(2, 5, 4, 7, 6); \
> +    ROW32(3, 5, 4, 7, 6);
> +
> +static void decode_mvc2(AVCodecContext *avctx, GetByteContext *gb, uint8_t
> *dst_start, int width, int height, int linesize, int vflip)
> +{

Why all functions return void? How would one detect if frame is
decoded or corrupted?
> +    uint8_t *dst;
> +    uint32_t color[128], v[8];
> +    int w, h, nb_colors, i, x, y, p0, p1, mask;
> +
> +    if (bytestream2_get_bytes_left(gb) < 6)
> +        return;
> +
> +    w = bytestream2_get_be16u(gb);
> +    h = bytestream2_get_be16u(gb);
> +    if ((w & ~3) != width || (h & ~3) != height)
> +        av_log(avctx, AV_LOG_WARNING, "dimension mismatch\n");
> +
> +    if (bytestream2_get_byteu(gb)) {
> +        av_log_ask_for_sample(avctx, "bitmap feature\n");
> +        return;
> +    }
> +
> +    nb_colors = bytestream2_get_byteu(gb);
> +    if (bytestream2_get_bytes_left(gb) < nb_colors * 3)
> +        return;
> +    for (i = 0; i < FFMIN(nb_colors, 128); i++)
> +        color[i] = 0xFF000000 | bytestream2_get_be24u(gb);
> +    if (nb_colors > 128)
> +        bytestream2_skip(gb, (nb_colors - 128) * 3);
> +
> +    if (vflip) {
> +        dst_start += (height - 1) * linesize;
> +        linesize = -linesize;
> +    }
> +    x = y = 0;
> +    while (bytestream2_get_bytes_left(gb) >= 1) {
> +        p0 = bytestream2_get_byteu(gb);
> +        if ((p0 & 0x80)) {
> +            if ((p0 & 0x40)) {
> +                p0 &= 0x3F;
> +                p0 = (p0 << 2) | (p0 >> 4);
> +                set_4x4_block(dst_start + y * linesize + x * 4, linesize,
> 0xFF000000 | (p0 << 16) | (p0 << 8) | p0);
> +            } else {
> +                int g, r;
> +                p0 &= 0x3F;
> +                p0 = (p0 << 2) | (p0 >> 4);
> +                if (bytestream2_get_bytes_left(gb) < 2)
> +                    return;
> +                g = bytestream2_get_byteu(gb);
> +                r = bytestream2_get_byteu(gb);
> +                set_4x4_block(dst_start + y * linesize + x * 4, linesize,
> 0xFF000000 | (r << 16) | (g << 8) | p0);
> +            }
> +        } else {
> +            if (bytestream2_get_bytes_left(gb) < 1)
> +                return;
> +            p1 = bytestream2_get_byteu(gb);
> +            if ((p1 & 0x80)) {
> +                if ((p0 & 0x7F) == (p1 & 0x7F)) {
> +                    set_4x4_block(dst_start + y * linesize + x * 4,
> linesize, color[p0 & 0x7F]);
> +                } else {
> +                    if (bytestream2_get_bytes_left(gb) < 2)
> +                        return;
> +                    v[0] = v[2] = v[4] = v[6] = color[p0 & 0x7F];
> +                    v[1] = v[3] = v[5] = v[7] = color[p1 & 0x7F];
> +                    mask = bytestream2_get_le16u(gb);
> +                    MVC2_BLOCK
> +                }
> +            } else {
> +                if (bytestream2_get_bytes_left(gb) < 8)
> +                    return;
> +                v[0] = color[p0 & 0x7F];
> +                v[1] = color[p1 & 0x7F];
> +                for (i = 2; i < 8; i++)
> +                    v[i] = color[bytestream2_get_byteu(gb) & 0x7F];
> +                mask = bytestream2_get_le16u(gb);
> +                MVC2_BLOCK
> +            }
> +        }
> +
> +        x += 4;
> +        if (x >= width) {
> +            y += 4;
> +            if (y >= height)
> +                break;
> +            x = 0;
> +        }
> +    }
> +}
> +
> +static int mvc_decode_frame(AVCodecContext *avctx,
> +                            void *data, int *data_size,

got_frame .....
> +                            AVPacket *avpkt)
> +{
> +    MvcContext *s = avctx->priv_data;
> +    GetByteContext gb;
> +
> +    s->frame.reference = 3;
> +    s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
> FF_BUFFER_HINTS_PRESERVE |
> +                            FF_BUFFER_HINTS_REUSABLE |
> FF_BUFFER_HINTS_READABLE;
> +    if (avctx->reget_buffer(avctx, &s->frame)) {
> +        av_log (avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
> +        return -1;

return meaningful error
> +    }
> +
> +    bytestream2_init(&gb, avpkt->data, avpkt->size);
> +    if (avctx->codec_id == AV_CODEC_ID_MVC1)
> +        decode_mvc1(avctx, &gb, s->frame.data[0], avctx->width,
> avctx->height, s->frame.linesize[0]);
> +    else
> +        decode_mvc2(avctx, &gb, s->frame.data[0], avctx->width,
> avctx->height, s->frame.linesize[0], s->vflip);

If decoding fails error is returned and *got_frame is 0.
> +
> +    *data_size = sizeof(AVFrame);

*got_frame = 1;
> +    *(AVFrame*)data = s->frame;
> +
> +    return avpkt->size;
> +}
> +
> +static av_cold int mvc_decode_end(AVCodecContext *avctx)
> +{
> +    MvcContext *s = avctx->priv_data;
> +
> +    if (s->frame.data[0])
> +        avctx->release_buffer(avctx, &s->frame);
> +
> +    return 0;
> +}
> +
> +#if CONFIG_MVC1_DECODER
> +AVCodec ff_mvc1_decoder = {
> +    .name           = "mvc1",
> +    .type           = AVMEDIA_TYPE_VIDEO,
> +    .id             = AV_CODEC_ID_MVC1,
> +    .priv_data_size = sizeof(MvcContext),
> +    .init           = mvc_decode_init,
> +    .close          = mvc_decode_end,
> +    .decode         = mvc_decode_frame,
> +    .capabilities   = CODEC_CAP_DR1,
> +    .long_name      = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video
> Compressor 1"),
> +};
> +#endif
> +
> +#if CONFIG_MVC1_DECODER
> +AVCodec ff_mvc2_decoder = {
> +    .name           = "mvc2",
> +    .type           = AVMEDIA_TYPE_VIDEO,
> +    .id             = AV_CODEC_ID_MVC2,
> +    .priv_data_size = sizeof(MvcContext),
> +    .init           = mvc_decode_init,
> +    .close          = mvc_decode_end,
> +    .decode         = mvc_decode_frame,
> +    .capabilities   = CODEC_CAP_DR1,
> +    .long_name      = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video
> Compressor 2"),
> +};
> +#endif
> --
> 1.8.0
>
> -- Peter
> (A907 E02F A6E5 0CD2 34CD 20D2 6760 79C5 AC40 DD6B)
>


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