[FFmpeg-devel] [PATCH] avcodec: add PhotoCD decoder

Paul B Mahol onemda at gmail.com
Sat Aug 29 23:35:23 EEST 2020


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;
+
+    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);
+        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"      },
-- 
2.17.1



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