FFmpeg/libavcodec/tiffenc.c

/*
 * TIFF image encoder
 * Copyright (c) 2007 Bartlomiej Wolowiec
 *
 * 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
 *
 */

#include "avcodec.h"
#ifdef CONFIG_ZLIB
#include <zlib.h>
#endif
#include "bytestream.h"
#include "tiff.h"
#include "rle.h"

#define TIFF_MAX_ENTRY 32

/** sizes of various TIFF field types (string size = 1)*/
static const uint8_t type_sizes2[6] = {
    0, 1, 1, 2, 4, 8
};

typedef struct TiffEncoderContext {
    AVCodecContext *avctx;
    AVFrame picture;

    int width;                          ///< picture width
    int height;                         ///< picture height
    unsigned int bpp;                   ///< bits per pixel
    int compr;                          ///< compression level
    int bpp_tab_size;                   ///< bpp_tab size
    int invert;                         ///< photometric interpretation
    int strips;                         ///< number of strips
    int rps;                            ///< row per strip
    uint8_t entries[TIFF_MAX_ENTRY*12]; ///< entires in header
    int num_entries;                    ///< number of entires
    uint8_t **buf;                      ///< actual position in buffer
    uint8_t *buf_start;                 ///< pointer to first byte in buffer
    int buf_size;                       ///< buffer size
} TiffEncoderContext;


/**
 * Check free space in buffer
 * @param s Tiff context
 * @param need Needed bytes
 * @return 0 - ok, 1 - no free space
 */
inline static int check_size(TiffEncoderContext * s, uint64_t need)
{
    if (s->buf_size < *s->buf - s->buf_start + need) {
        *s->buf = s->buf_start + s->buf_size + 1;
        av_log(s->avctx, AV_LOG_ERROR, "Buffer is too small\n");
        return 1;
    }
    return 0;
}

/**
 * Put n values to buffer
 *
 * @param p Pointer to pointer to output buffer
 * @param n Number of values
 * @param val Pointer to values
 * @param type Type of values
 * @param flip =0 - normal copy, >0 - flip
 */
static void tnput(uint8_t ** p, int n, const uint8_t * val, enum TiffTypes type,
                  int flip)
{
    int i;
#ifdef WORDS_BIGENDIAN
    flip ^= ((int[]) {0, 0, 0, 1, 3, 3})[type];
#endif
    for (i = 0; i < n * type_sizes2[type]; i++)
        *(*p)++ = val[i ^ flip];
}

/**
 * Add entry to directory in tiff header.
 * @param s Tiff context
 * @param tag Tag that identifies the entry
 * @param type Entry type
 * @param count The number of values
 * @param ptr_val Pointer to values
 */
static void add_entry(TiffEncoderContext * s,
                      enum TiffTags tag, enum TiffTypes type, int count,
                      const void *ptr_val)
{
    uint8_t *entries_ptr = s->entries + 12 * s->num_entries;

    assert(s->num_entries < TIFF_MAX_ENTRY);

    bytestream_put_le16(&entries_ptr, tag);
    bytestream_put_le16(&entries_ptr, type);
    bytestream_put_le32(&entries_ptr, count);

    if (type_sizes[type] * count <= 4) {
        tnput(&entries_ptr, count, ptr_val, type, 0);
    } else {
        bytestream_put_le32(&entries_ptr, *s->buf - s->buf_start);
        check_size(s, count * type_sizes2[type]);
        tnput(s->buf, count, ptr_val, type, 0);
    }

    s->num_entries++;
}

/**
 * Encode one strip in tiff file
 *
 * @param s Tiff context
 * @param src Input buffer
 * @param dst Output buffer
 * @param n Size of input buffer
 * @param compr Compression method
 * @return Number of output bytes. If an output error is encountered, -1 returned
 */
static int encode_strip(TiffEncoderContext * s, const int8_t * src,
                        uint8_t * dst, int n, int compr)
{

    switch (compr) {
#ifdef CONFIG_ZLIB
    case TIFF_DEFLATE:
    case TIFF_ADOBE_DEFLATE:
        {
            unsigned long zlen = s->buf_size - (*s->buf - s->buf_start);
            if (compress(dst, &zlen, src, n) != Z_OK) {
                av_log(s->avctx, AV_LOG_ERROR, "Compressing failed\n");
                return -1;
            }
            return zlen;
        }
#endif
    case TIFF_RAW:
        if (check_size(s, n))
            return -1;
        memcpy(dst, src, n);
        return n;
    case TIFF_PACKBITS:
        return ff_rle_encode(dst, s->buf_size - (*s->buf - s->buf_start), src, 1, n, 2, 0xff, -1, 0);
    default:
        return -1;
    }
}

static int encode_frame(AVCodecContext * avctx, unsigned char *buf,
                        int buf_size, void *data)
{
    TiffEncoderContext *s = avctx->priv_data;
    AVFrame *pict = data;
    AVFrame *const p = (AVFrame *) & s->picture;
    int i;
    int n;
    uint8_t *ptr = buf;
    uint8_t *offset;
    uint32_t strips;
    uint32_t *strip_sizes = NULL;
    uint32_t *strip_offsets = NULL;
    int bytes_per_row;
    uint32_t res[2] = { 72, 1 };        // image resolution (72/1)
    static const uint16_t bpp_tab[] = { 8, 8, 8, 8 };
    int ret = -1;

    s->buf_start = buf;
    s->buf = &ptr;
    s->buf_size = buf_size;

    *p = *pict;
    p->pict_type = FF_I_TYPE;
    p->key_frame = 1;

    s->compr = TIFF_PACKBITS;
    if (avctx->compression_level == 0) {
        s->compr = TIFF_RAW;
#ifdef CONFIG_ZLIB
    } else if ((avctx->compression_level > 2)) {
        s->compr = TIFF_DEFLATE;
#endif
    }

    s->width = avctx->width;
    s->height = avctx->height;

    switch (avctx->pix_fmt) {
    case PIX_FMT_RGB24:
        s->bpp = 24;
        s->invert = 2;
        break;
    case PIX_FMT_GRAY8:
        s->bpp = 8;
        s->invert = 1;
        break;
    case PIX_FMT_PAL8:
        s->bpp = 8;
        s->invert = 3;
        break;
    case PIX_FMT_MONOBLACK:
        s->bpp = 1;
        s->invert = 1;
        break;
    case PIX_FMT_MONOWHITE:
        s->bpp = 1;
        s->invert = 0;
        break;
    default:
        av_log(s->avctx, AV_LOG_ERROR,
               "This colors format is not supported\n");
        return -1;
    }
    s->bpp_tab_size = (s->bpp >> 3);

    if (s->compr == TIFF_DEFLATE || s->compr == TIFF_ADOBE_DEFLATE)
        //best choose for DEFLATE
        s->rps = s->height;
    else
        s->rps = FFMAX(8192 / (((s->width * s->bpp) >> 3) + 1), 1);     // suggest size of strip

    strips = (s->height - 1) / s->rps + 1;

    if (check_size(s, 8))
        goto fail;

    // write header
    bytestream_put_le16(&ptr, 0x4949);
    bytestream_put_le16(&ptr, 42);

    offset = ptr;
    bytestream_put_le32(&ptr, 0);

    strip_sizes = av_mallocz(sizeof(*strip_sizes) * strips);
    strip_offsets = av_mallocz(sizeof(*strip_offsets) * strips);

    bytes_per_row = (s->width * s->bpp + 7) >> 3;

#ifdef CONFIG_ZLIB
    if (s->compr == TIFF_DEFLATE || s->compr == TIFF_ADOBE_DEFLATE) {
        uint8_t *zbuf;
        int zlen, zn;
        int j;

        zlen = bytes_per_row * s->rps;
        zbuf = av_malloc(zlen);
        strip_offsets[0] = ptr - buf;
        zn = 0;
        for (j = 0; j < s->rps; j++) {
            memcpy(zbuf + j * bytes_per_row,
                   p->data[0] + j * p->linesize[0], bytes_per_row);
            zn += bytes_per_row;
        }
        n = encode_strip(s, zbuf, ptr, zn, s->compr);
        av_free(zbuf);
        if (n<0) {
            av_log(s->avctx, AV_LOG_ERROR, "Encode strip failed\n");
            goto fail;
        }
        ptr += n;
        strip_sizes[0] = ptr - buf - strip_offsets[0];
    } else
#endif
    {
        for (i = 0; i < s->height; i++) {
            if (strip_sizes[i / s->rps] == 0) {
                strip_offsets[i / s->rps] = ptr - buf;
            }
            if ((n = encode_strip(s, p->data[0] + i * p->linesize[0]
                                  , ptr, bytes_per_row, s->compr)) < 0) {
                av_log(s->avctx, AV_LOG_ERROR, "Encode strip failed\n");
                goto fail;
            }
            strip_sizes[i / s->rps] += n;
            ptr += n;
        }
    }

    s->num_entries = 0;

    add_entry(s, TIFF_SUBFILE,           TIFF_LONG,     1,      (uint32_t[]) {0});
    add_entry(s, TIFF_WIDTH,             TIFF_LONG,     1,      (uint32_t[]) {s->width});
    add_entry(s, TIFF_HEIGHT,            TIFF_LONG,     1,      (uint32_t[]) {s->height});

    if (s->bpp_tab_size)
    add_entry(s, TIFF_BPP,               TIFF_SHORT,    s->bpp_tab_size, bpp_tab);

    add_entry(s, TIFF_COMPR,             TIFF_SHORT,    1,      (uint16_t[]) {s->compr});
    add_entry(s, TIFF_INVERT,            TIFF_SHORT,    1,      (uint16_t[]) {s->invert});
    add_entry(s, TIFF_STRIP_OFFS,        TIFF_LONG,     strips, strip_offsets);

    if (s->bpp_tab_size)
    add_entry(s, TIFF_SAMPLES_PER_PIXEL, TIFF_SHORT,    1,      (uint16_t[]) {s->bpp_tab_size});

    add_entry(s, TIFF_ROWSPERSTRIP,      TIFF_LONG,     1,      (uint32_t[]) {s->rps});
    add_entry(s, TIFF_STRIP_SIZE,        TIFF_LONG,     strips, strip_sizes);
    add_entry(s, TIFF_XRES,              TIFF_RATIONAL, 1,      res);
    add_entry(s, TIFF_YRES,              TIFF_RATIONAL, 1,      res);
    add_entry(s, TIFF_RES_UNIT,          TIFF_SHORT,    1,      (uint16_t[]) {2});
    add_entry(s, TIFF_SOFTWARE_NAME,     TIFF_STRING,
              strlen(LIBAVCODEC_IDENT) + 1, LIBAVCODEC_IDENT);

    if (avctx->pix_fmt == PIX_FMT_PAL8) {
        uint16_t pal[256 * 3];
        for (i = 0; i < 256; i++) {
            uint32_t rgb = *(uint32_t *) (p->data[1] + i * 4);
            pal[i]       = ((rgb >> 16) & 0xff) * 257;
            pal[i + 256] = ((rgb >> 8 ) & 0xff) * 257;
            pal[i + 512] = ( rgb        & 0xff) * 257;
        }
        add_entry(s, TIFF_PAL, TIFF_SHORT, 256 * 3, pal);
    }
    bytestream_put_le32(&offset, ptr - buf);    // write offset to dir

    if (check_size(s, 6 + s->num_entries * 12))
        goto fail;
    bytestream_put_le16(&ptr, s->num_entries);  // write tag count
    bytestream_put_buffer(&ptr, s->entries, s->num_entries * 12);
    bytestream_put_le32(&ptr, 0);

    ret = ptr - buf;

fail:
    av_free(strip_sizes);
    av_free(strip_offsets);
    return ret;
}

AVCodec tiff_encoder = {
    "tiff",
    CODEC_TYPE_VIDEO,
    CODEC_ID_TIFF,
    sizeof(TiffEncoderContext),
    NULL,
    encode_frame,
    NULL,
    NULL,
    0,
    NULL,
    .pix_fmts =
        (enum PixelFormat[]) {PIX_FMT_RGB24, PIX_FMT_PAL8, PIX_FMT_GRAY8,
                              PIX_FMT_MONOBLACK, PIX_FMT_MONOWHITE,
                              -1}

};