[FFmpeg-devel] [PATCH] avcodec: add PhotoCD decoder
Andreas Rheinhardt
andreas.rheinhardt at gmail.com
Sun Aug 30 05:40:32 EEST 2020
Paul B Mahol:
> Signed-off-by: Paul B Mahol <onemda at gmail.com>
> ---
> Probably need to be applied on top of moflex v2 patch set.
> ---
> libavcodec/Makefile | 1 +
> libavcodec/allcodecs.c | 1 +
> libavcodec/codec_desc.c | 7 +
> libavcodec/codec_id.h | 1 +
> libavcodec/photocd.c | 468 ++++++++++++++++++++++++++++++++++++++++
> libavformat/img2.c | 1 +
> 6 files changed, 479 insertions(+)
> create mode 100644 libavcodec/photocd.c
>
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index 97fbe6b7a9..98f31e246b 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -541,6 +541,7 @@ OBJS-$(CONFIG_PGMYUV_DECODER) += pnmdec.o pnm.o
> OBJS-$(CONFIG_PGMYUV_ENCODER) += pnmenc.o
> OBJS-$(CONFIG_PGSSUB_DECODER) += pgssubdec.o
> OBJS-$(CONFIG_PGX_DECODER) += pgxdec.o
> +OBJS-$(CONFIG_PHOTOCD_DECODER) += photocd.o
> OBJS-$(CONFIG_PICTOR_DECODER) += pictordec.o cga_data.o
> OBJS-$(CONFIG_PIXLET_DECODER) += pixlet.o
> OBJS-$(CONFIG_PJS_DECODER) += textdec.o ass.o
> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
> index 8a4b3fb178..f3572a47e3 100644
> --- a/libavcodec/allcodecs.c
> +++ b/libavcodec/allcodecs.c
> @@ -241,6 +241,7 @@ extern AVCodec ff_pgm_decoder;
> extern AVCodec ff_pgmyuv_encoder;
> extern AVCodec ff_pgmyuv_decoder;
> extern AVCodec ff_pgx_decoder;
> +extern AVCodec ff_photocd_decoder;
> extern AVCodec ff_pictor_decoder;
> extern AVCodec ff_pixlet_decoder;
> extern AVCodec ff_png_encoder;
> diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
> index ceef244ebf..9e73dcba27 100644
> --- a/libavcodec/codec_desc.c
> +++ b/libavcodec/codec_desc.c
> @@ -1791,6 +1791,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
> .long_name = NULL_IF_CONFIG_SMALL("MobiClip Video"),
> .props = AV_CODEC_PROP_LOSSY,
> },
> + {
> + .id = AV_CODEC_ID_PHOTOCD,
> + .type = AVMEDIA_TYPE_VIDEO,
> + .name = "photocd",
> + .long_name = NULL_IF_CONFIG_SMALL("Kodak Photo CD"),
> + .props = AV_CODEC_PROP_LOSSY,
> + },
>
> /* various PCM "codecs" */
> {
> diff --git a/libavcodec/codec_id.h b/libavcodec/codec_id.h
> index 19d5014bb4..e4eca5d580 100644
> --- a/libavcodec/codec_id.h
> +++ b/libavcodec/codec_id.h
> @@ -297,6 +297,7 @@ enum AVCodecID {
> AV_CODEC_ID_NOTCHLC,
> AV_CODEC_ID_PFM,
> AV_CODEC_ID_MOBICLIP,
> + AV_CODEC_ID_PHOTOCD,
>
> /* various PCM "codecs" */
> AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
> diff --git a/libavcodec/photocd.c b/libavcodec/photocd.c
> new file mode 100644
> index 0000000000..50584ac980
> --- /dev/null
> +++ b/libavcodec/photocd.c
> @@ -0,0 +1,468 @@
> +/*
> + * Kodak PhotoCD (a.k.a. ImagePac) image decoder
> + *
> + * Copyright (c) 1996-2002 Gerd Knorr
> + * Copyright (c) 2010 Kenneth Vermeirsch
> + * Copyright (c) 2020 Paul B Mahol
> + *
> + * 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
> + * Kodak PhotoCD (a.k.a. ImagePac) image decoder
> + *
> + * Supports resolutions up to 3072x2048.
> + */
> +
> +#include "libavutil/avassert.h"
> +#include "libavutil/intreadwrite.h"
> +#include "libavutil/opt.h"
> +#include "avcodec.h"
> +#include "bytestream.h"
> +#include "get_bits.h"
> +#include "internal.h"
> +
> +typedef struct PhotoCDContext {
> + AVClass *class;
> + int lowres;
> +
> + GetByteContext gb;
> + int thumbnails; //* number of thumbnails; 0 for normal image */
> + int resolution;
> + int orientation;
> +
> + int streampos;
> +
> + uint8_t bits[256];
> + uint16_t codes[256];
> + uint8_t syms[256];
> +
> + VLC vlc[3];
> +} PhotoCDContext;
> +
> +typedef struct ImageInfo {
> + uint32_t start;
> + uint16_t width, height;
> +} ImageInfo;
> +
> +static const ImageInfo img_info[6] = {
> + {8192, 192, 128},
> + {47104, 384, 256},
> + {196608, 768, 512},
> + {0, 1536, 1024},
> + {0, 3072, 2048},
> + {0, 6144, 4096},
> +};
> +
> +static av_always_inline void interp_lowres(PhotoCDContext *s, AVFrame *picture,
> + int width, int height)
> +{
> + GetByteContext *gb = &s->gb;
> + int start = s->streampos + img_info[2].start;
> + uint8_t *ptr, *ptr1, *ptr2;
> + uint8_t *dest;
> + int fill;
> +
> + ptr = picture->data[0];
> + ptr1 = picture->data[1];
> + ptr2 = picture->data[2];
> +
> + bytestream2_seek(gb, start, SEEK_SET);
> +
> + for (int y = 0; y < height; y += 2) {
> + dest = ptr;
> + for (int x = 0; x < width - 1; x++) {
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = (fill + bytestream2_peek_byte(gb) + 1) >> 1;
> + }
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = fill;
> +
> + ptr += picture->linesize[0] << 1;
> +
> + dest = ptr;
> + for (int x = 0; x < width - 1; x++) {
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = (fill + bytestream2_peek_byte(gb) + 1) >> 1;
> + }
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = fill;
> +
> + ptr += picture->linesize[0] << 1;
> +
> + dest = ptr1;
> + for (int x = 0; x < (width >> 1) - 1; x++) {
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = (fill + bytestream2_peek_byte(gb) + 1) >> 1;
> + }
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = fill;
> +
> + ptr1 += picture->linesize[1] << 1;
> +
> + dest = ptr2;
> + for (int x = 0; x < (width >> 1) - 1; x++) {
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = (fill + bytestream2_peek_byte(gb) + 1) >> 1;
> + }
> + fill = bytestream2_get_byte(gb);
> + *(dest++) = fill;
> + *(dest++) = fill;
> +
> + ptr2 += picture->linesize[2] << 1;
> + }
> +
> + s->streampos += bytestream2_tell(gb) - start;
> +}
> +
> +static void interp_lines(uint8_t *ptr, int linesize, int width, int height)
> +{
> + uint8_t *src1, *src2, *dest;
> + int x;
> +
> + for (int y = 0; y < height - 2; y += 2) {
> + src1 = ptr;
> + dest = src1 + linesize;
> + src2 = dest + linesize;
> + for (x = 0; x < width - 2; x += 2) {
> + dest[x] = (src1[x] + src2[x] + 1) >> 1;
> + dest[x + 1] = (src1[x] + src2[x] + src1[x + 2] + src2[x + 2] + 2) >> 2;
> + }
> + dest[x] = dest[x + 1] = (src1[x] + src2[x] + 1) >> 1;
> +
> + ptr += linesize << 1;
> + }
> +
> + src1 = ptr;
> + dest = ptr + linesize;
> + for (x = 0; x < width - 2; x += 2) {
> + dest[x] = src1[x];
> + dest[x + 1] = (src1[x] + src1[x + 2] + 1) >> 1;
> + }
> + dest[x] = dest[x + 1] = src1[x];
> +}
> +
> +static void interp_pixels(uint8_t *ptr, int linesize, int width, int height)
> +{
> + uint8_t *src, *dest;
> +
> + for (int y = height - 2; y >= 0; y -= 2) {
> + src = ptr + (y >> 1) * linesize;
> + dest = ptr + y * linesize;
> +
> + dest[width - 2] = dest[width - 1] = src[(width >> 1) - 1];
> + for (int x = width - 4; x >= 0; x -= 2) {
> + dest[x] = src[x >> 1];
> + dest[x + 1] = (src[x >> 1] + src[(x >> 1) + 1] + 1) >> 1;
> + }
> + }
> +}
> +
> +static int read_hufftable(AVCodecContext *avctx, VLC *vlc)
> +{
> + PhotoCDContext *s = avctx->priv_data;
> + GetByteContext *gb = &s->gb;
> + int start = s->streampos;
> + int count, ret;
> +
> + bytestream2_seek(gb, start, SEEK_SET);
> +
> + count = bytestream2_get_byte(gb) + 1;
> +
With this information you can check once whether there is enough data
left, allowing you to use the unchecked versions of the bytestream2 API.
> + ff_free_vlc(vlc);
> +
> + for (int j = 0; j < count; j++) {
> + const int bit = bytestream2_get_byte(gb) + 1;
> + const int code = bytestream2_get_be16(gb) >> (16 - bit);
You are using bit here before having validated it.
> + const int sym = bytestream2_get_byte(gb);
> +
> + if (bit > 16)
> + return AVERROR_INVALIDDATA;
> +
> + s->bits[j] = bit;
> + s->codes[j] = code;
> + s->syms[j] = sym;
> + }
> +
> + ret = ff_init_vlc_sparse(vlc, 12, count,
> + s->bits, sizeof(*s->bits), sizeof(*s->bits),
> + s->codes, sizeof(*s->codes), sizeof(*s->codes),
> + s->syms, sizeof(*s->syms), sizeof(*s->syms), 0);
> +
> + s->streampos = bytestream2_tell(gb);
> +
> + return ret;
> +}
> +
> +static int decode_huff(AVCodecContext *avctx, AVFrame *frame,
> + int target_res, int curr_res)
> +{
> + PhotoCDContext *s = avctx->priv_data;
> + GetBitContext g;
> + GetByteContext *gb = &s->gb;
> + int ret, y = 0, type, height, y2;
> + int start = s->streampos;
> + unsigned shiftreg, bit;
> + const int scaling = target_res - curr_res;
> + const uint8_t type2idx[] = { 0, 0xff, 1, 2 };
> +
> + bytestream2_seek(gb, start, SEEK_SET);
> + ret = init_get_bits8(&g, gb->buffer, bytestream2_get_bytes_left(gb));
> + if (ret < 0)
> + return ret;
> +
> + height = img_info[curr_res].height;
> + y2 = avctx->height >> scaling;
> +
> + while (y < height) {
> + uint8_t *data;
> + int x2, idx;
> +
> + bit = 0;
> + for (; get_bits_left(&g) > 0;) {
> + if ((show_bits_long(&g, 32) & 0x00fff000) == 0xfff000)
> + break;
> + skip_bits(&g, 8);
> + }
> +
> + shiftreg = show_bits_long(&g, 32) & 0xffffff00;
> + while (shiftreg != 0xfffffe00) {
> + if (get_bits_left(&g) <= 0)
> + return AVERROR_INVALIDDATA;
> + skip_bits(&g, 1);
> + shiftreg = show_bits_long(&g, 32) & 0xffffff00;
> + }
> + skip_bits(&g, 16);
> + y = (show_bits_long(&g, 32) >> 9) & 0x1fff;
> + skip_bits(&g, 8);
> + if (y >= height)
> + break;
> + type = get_bits(&g, 2);
> + skip_bits(&g, 14);
> +
> + if (type == 1)
> + return AVERROR_INVALIDDATA;
> + idx = type2idx[type];
> +
> + data = frame->data[idx] + (y >> !!idx) * frame->linesize[idx];
> +
> + x2 = avctx->width >> (scaling + !!idx);
> + for (int x = 0; x < x2; x++) {
> + int m;
> +
> + if (get_bits_left(&g) <= 0)
> + return AVERROR_INVALIDDATA;
> + m = get_vlc2(&g, s->vlc[idx].table, s->vlc[idx].bits, 2);
> + if (m < 0)
> + return AVERROR_INVALIDDATA;
> + m = sign_extend(m, 8);
> + data[x] = av_clip_uint8(data[x] + m);
> + }
> + }
> +
> + s->streampos += (get_bits_count(&g) + 7) >> 3;
> + s->streampos = (s->streampos + 0x6000 + 2047) & ~0x7ff;
> +
> + return 0;
> +}
> +
> +static int photocd_decode_frame(AVCodecContext *avctx, void *data,
> + int *got_frame, AVPacket *avpkt)
> +{
> + PhotoCDContext *s = avctx->priv_data;
> + const uint8_t *buf = avpkt->data;
> + GetByteContext *gb = &s->gb;
> + AVFrame *p = data;
> + uint8_t *ptr, *ptr1, *ptr2;
> + int ret;
> +
> + if (avpkt->size < img_info[0].start)
> + return AVERROR_INVALIDDATA;
> +
> + if (!memcmp("PCD_OPA", buf, 7)) {
> + s->thumbnails = AV_RL16(buf + 10);
> + av_log(avctx, AV_LOG_WARNING, "this is a thumbnails file, "
> + "reading first thumbnail only\n");
> + } else if (avpkt->size < 786432) {
> + return AVERROR_INVALIDDATA;
> + } else if (memcmp("PCD_IPI", buf + 0x800, 7)) {
> + return AVERROR_INVALIDDATA;
> + }
> +
> + s->orientation = s->thumbnails ? buf[12] & 3 : buf[0x48] & 3;
> +
> + if (s->thumbnails)
> + s->resolution = 0;
> + else if (avpkt->size <= 788480)
> + s->resolution = 2;
> + else
> + s->resolution = av_clip(4 - s->lowres, 0, 4);
> +
> + avctx->width = img_info[s->resolution].width;
> + avctx->height = img_info[s->resolution].height;
> +
> + if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
> + return ret;
> + p->pict_type = AV_PICTURE_TYPE_I;
> + p->key_frame = 1;
> +
> + bytestream2_init(gb, avpkt->data, avpkt->size);
> +
> + if (s->resolution < 3) {
> + ptr = p->data[0];
> + ptr1 = p->data[1];
> + ptr2 = p->data[2];
> +
> + if (s->thumbnails) {
> + bytestream2_seek(gb, 10240, SEEK_SET);
> + } else {
> + bytestream2_seek(gb, img_info[s->resolution].start, SEEK_SET);
> + }
> +
> + for (int y = 0; y < avctx->height; y += 2) {
> + bytestream2_get_buffer(gb, ptr, avctx->width);
> + ptr += p->linesize[0];
> +
> + bytestream2_get_buffer(gb, ptr, avctx->width);
> + ptr += p->linesize[0];
> +
> + bytestream2_get_buffer(gb, ptr1, avctx->width >> 1);
> + ptr1 += p->linesize[1];
> +
> + bytestream2_get_buffer(gb, ptr2, avctx->width >> 1);
> + ptr2 += p->linesize[2];
> + }
> + } else {
> + s->streampos = 0;
> + ptr = p->data[0];
> + ptr1 = p->data[1];
> + ptr2 = p->data[2];
> +
> + interp_lowres(s, p, img_info[2].width, img_info[2].height);
> +
> + interp_lines(ptr1, p->linesize[1], img_info[2].width, img_info[2].height);
> + interp_lines(ptr2, p->linesize[2], img_info[2].width, img_info[2].height);
> +
> + if (s->resolution == 4) {
> + interp_pixels(ptr1, p->linesize[1], img_info[3].width, img_info[3].height);
> + interp_lines (ptr1, p->linesize[1], img_info[3].width, img_info[3].height);
> + interp_pixels(ptr2, p->linesize[2], img_info[3].width, img_info[3].height);
> + interp_lines (ptr2, p->linesize[2], img_info[3].width, img_info[3].height);
> + }
> +
> + interp_lines(ptr, p->linesize[0], img_info[3].width, img_info[3].height);
> +
> + s->streampos = 0xc2000;
> + for (int n = 0; n < 3; n++) {
> + if ((ret = read_hufftable(avctx, &s->vlc[n])) < 0)
> + return ret;
> + }
> + s->streampos = (s->streampos + 2047) & ~0x3ff;
> + if (decode_huff(avctx, p, s->resolution, 3) < 0)
> + return AVERROR_INVALIDDATA;
> +
> + if (s->resolution == 4) {
> + interp_pixels(ptr, p->linesize[0], img_info[4].width, img_info[4].height);
> + interp_lines (ptr, p->linesize[0], img_info[4].width, img_info[4].height);
> +
> + for (int n = 0; n < 3; n++) {
> + if ((ret = read_hufftable(avctx, &s->vlc[n])) < 0)
> + return ret;
> + }
> + s->streampos = (s->streampos + 2047) & ~0x3ff;
> + if (decode_huff(avctx, p, 4, 4) < 0)
> + return AVERROR_INVALIDDATA;
> + }
> + }
> +
> + {
> + ptr1 = p->data[1];
> + ptr2 = p->data[2];
> +
> + for (int y = 0; y < avctx->height >> 1; y++) {
> + for (int x = 0; x < avctx->width >> 1; x++) {
> + ptr1[x] = av_clip_uint8(ptr1[x] - 28);
> + ptr2[x] = av_clip_uint8(ptr2[x] - 9);
> + }
> +
> + ptr1 += p->linesize[1];
> + ptr2 += p->linesize[2];
> + }
> + }
> +
> + *got_frame = 1;
> +
> + return 0;
> +}
> +
> +static av_cold int photocd_decode_init(AVCodecContext *avctx)
> +{
> + avctx->pix_fmt = AV_PIX_FMT_YUV420P;
> + avctx->colorspace = AVCOL_SPC_BT709;
> + avctx->color_primaries = AVCOL_PRI_BT709;
> + avctx->color_trc = AVCOL_TRC_IEC61966_2_4;
> + avctx->color_range = AVCOL_RANGE_MPEG;
> +
> + return 0;
> +}
> +
> +static av_cold int photocd_decode_close(AVCodecContext *avctx)
> +{
> + PhotoCDContext *s = avctx->priv_data;
> +
> + for (int i = 0; i < 3; i++)
> + ff_free_vlc(&s->vlc[i]);
> +
> + return 0;
> +}
> +
> +#define OFFSET(x) offsetof(PhotoCDContext, x)
> +#define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
> +
> +static const AVOption options[] = {
> + { "lowres", "Lower the decoding resolution by a power of two",
> + OFFSET(lowres), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 4, VD },
> + { NULL },
> +};
> +
> +static const AVClass photocd_class = {
> + .class_name = "photocd",
> + .item_name = av_default_item_name,
> + .option = options,
> + .version = LIBAVUTIL_VERSION_INT,
> +};
> +
> +AVCodec ff_photocd_decoder = {
> + .name = "photocd",
> + .type = AVMEDIA_TYPE_VIDEO,
> + .id = AV_CODEC_ID_PHOTOCD,
> + .priv_data_size = sizeof (PhotoCDContext),
> + .priv_class = &photocd_class,
> + .init = photocd_decode_init,
> + .close = photocd_decode_close,
> + .decode = photocd_decode_frame,
> + .capabilities = AV_CODEC_CAP_DR1,
> + .long_name = NULL_IF_CONFIG_SMALL("Kodak Photo CD"),
> +};
> diff --git a/libavformat/img2.c b/libavformat/img2.c
> index d243d6c125..db37aa7228 100644
> --- a/libavformat/img2.c
> +++ b/libavformat/img2.c
> @@ -55,6 +55,7 @@ const IdStrMap ff_img_tags[] = {
> { AV_CODEC_ID_TIFF, "dng" },
> { AV_CODEC_ID_SGI, "sgi" },
> { AV_CODEC_ID_PTX, "ptx" },
> + { AV_CODEC_ID_PHOTOCD, "pcd" },
> { AV_CODEC_ID_PCX, "pcx" },
> { AV_CODEC_ID_QDRAW, "pic" },
> { AV_CODEC_ID_QDRAW, "pct" },
>
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