/* * PNG image format * Copyright (c) 2003 Fabrice Bellard * * 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" #include "codec_internal.h" #include "encode.h" #include "bytestream.h" #include "lossless_videoencdsp.h" #include "png.h" #include "apng.h" #include "zlib_wrapper.h" #include "libavutil/avassert.h" #include "libavutil/crc.h" #include "libavutil/csp.h" #include "libavutil/libm.h" #include "libavutil/mastering_display_metadata.h" #include "libavutil/opt.h" #include "libavutil/rational.h" #include "libavutil/stereo3d.h" #include #define IOBUF_SIZE 4096 typedef struct APNGFctlChunk { uint32_t sequence_number; uint32_t width, height; uint32_t x_offset, y_offset; uint16_t delay_num, delay_den; uint8_t dispose_op, blend_op; } APNGFctlChunk; typedef struct PNGEncContext { AVClass *class; LLVidEncDSPContext llvidencdsp; uint8_t *bytestream; uint8_t *bytestream_start; uint8_t *bytestream_end; int filter_type; FFZStream zstream; uint8_t buf[IOBUF_SIZE]; int dpi; ///< Physical pixel density, in dots per inch, if set int dpm; ///< Physical pixel density, in dots per meter, if set int is_progressive; int bit_depth; int color_type; int bits_per_pixel; // APNG uint32_t palette_checksum; // Used to ensure a single unique palette uint32_t sequence_number; int extra_data_updated; uint8_t *extra_data; int extra_data_size; AVFrame *prev_frame; AVFrame *last_frame; APNGFctlChunk last_frame_fctl; uint8_t *last_frame_packet; size_t last_frame_packet_size; } PNGEncContext; static void png_get_interlaced_row(uint8_t *dst, int row_size, int bits_per_pixel, int pass, const uint8_t *src, int width) { int x, mask, dst_x, j, b, bpp; uint8_t *d; const uint8_t *s; static const int masks[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; mask = masks[pass]; switch (bits_per_pixel) { case 1: memset(dst, 0, row_size); dst_x = 0; for (x = 0; x < width; x++) { j = (x & 7); if ((mask << j) & 0x80) { b = (src[x >> 3] >> (7 - j)) & 1; dst[dst_x >> 3] |= b << (7 - (dst_x & 7)); dst_x++; } } break; default: bpp = bits_per_pixel >> 3; d = dst; s = src; for (x = 0; x < width; x++) { j = x & 7; if ((mask << j) & 0x80) { memcpy(d, s, bpp); d += bpp; } s += bpp; } break; } } static void sub_png_paeth_prediction(uint8_t *dst, const uint8_t *src, const uint8_t *top, int w, int bpp) { int i; for (i = 0; i < w; i++) { int a, b, c, p, pa, pb, pc; a = src[i - bpp]; b = top[i]; c = top[i - bpp]; p = b - c; pc = a - c; pa = abs(p); pb = abs(pc); pc = abs(p + pc); if (pa <= pb && pa <= pc) p = a; else if (pb <= pc) p = b; else p = c; dst[i] = src[i] - p; } } static void sub_left_prediction(PNGEncContext *c, uint8_t *dst, const uint8_t *src, int bpp, int size) { const uint8_t *src1 = src + bpp; const uint8_t *src2 = src; int x, unaligned_w; memcpy(dst, src, bpp); dst += bpp; size -= bpp; unaligned_w = FFMIN(32 - bpp, size); for (x = 0; x < unaligned_w; x++) *dst++ = *src1++ - *src2++; size -= unaligned_w; c->llvidencdsp.diff_bytes(dst, src1, src2, size); } static void png_filter_row(PNGEncContext *c, uint8_t *dst, int filter_type, const uint8_t *src, const uint8_t *top, int size, int bpp) { int i; switch (filter_type) { case PNG_FILTER_VALUE_NONE: memcpy(dst, src, size); break; case PNG_FILTER_VALUE_SUB: sub_left_prediction(c, dst, src, bpp, size); break; case PNG_FILTER_VALUE_UP: c->llvidencdsp.diff_bytes(dst, src, top, size); break; case PNG_FILTER_VALUE_AVG: for (i = 0; i < bpp; i++) dst[i] = src[i] - (top[i] >> 1); for (; i < size; i++) dst[i] = src[i] - ((src[i - bpp] + top[i]) >> 1); break; case PNG_FILTER_VALUE_PAETH: for (i = 0; i < bpp; i++) dst[i] = src[i] - top[i]; sub_png_paeth_prediction(dst + i, src + i, top + i, size - i, bpp); break; } } static uint8_t *png_choose_filter(PNGEncContext *s, uint8_t *dst, const uint8_t *src, const uint8_t *top, int size, int bpp) { int pred = s->filter_type; av_assert0(bpp || !pred); if (!top && pred) pred = PNG_FILTER_VALUE_SUB; if (pred == PNG_FILTER_VALUE_MIXED) { int i; int cost, bcost = INT_MAX; uint8_t *buf1 = dst, *buf2 = dst + size + 16; for (pred = 0; pred < 5; pred++) { png_filter_row(s, buf1 + 1, pred, src, top, size, bpp); buf1[0] = pred; cost = 0; for (i = 0; i <= size; i++) cost += abs((int8_t) buf1[i]); if (cost < bcost) { bcost = cost; FFSWAP(uint8_t *, buf1, buf2); } } return buf2; } else { png_filter_row(s, dst + 1, pred, src, top, size, bpp); dst[0] = pred; return dst; } } static void png_write_chunk(uint8_t **f, uint32_t tag, const uint8_t *buf, int length) { const AVCRC *crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE); uint32_t crc = ~0U; uint8_t tagbuf[4]; bytestream_put_be32(f, length); AV_WL32(tagbuf, tag); crc = av_crc(crc_table, crc, tagbuf, 4); bytestream_put_be32(f, av_bswap32(tag)); if (length > 0) { crc = av_crc(crc_table, crc, buf, length); if (*f != buf) memcpy(*f, buf, length); *f += length; } bytestream_put_be32(f, ~crc); } static void png_write_image_data(AVCodecContext *avctx, const uint8_t *buf, int length) { PNGEncContext *s = avctx->priv_data; const AVCRC *crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE); uint32_t crc = ~0U; if (avctx->codec_id == AV_CODEC_ID_PNG || avctx->frame_num == 0) { png_write_chunk(&s->bytestream, MKTAG('I', 'D', 'A', 'T'), buf, length); return; } bytestream_put_be32(&s->bytestream, length + 4); bytestream_put_be32(&s->bytestream, MKBETAG('f', 'd', 'A', 'T')); bytestream_put_be32(&s->bytestream, s->sequence_number); crc = av_crc(crc_table, crc, s->bytestream - 8, 8); crc = av_crc(crc_table, crc, buf, length); memcpy(s->bytestream, buf, length); s->bytestream += length; bytestream_put_be32(&s->bytestream, ~crc); ++s->sequence_number; } /* XXX: do filtering */ static int png_write_row(AVCodecContext *avctx, const uint8_t *data, int size) { PNGEncContext *s = avctx->priv_data; z_stream *const zstream = &s->zstream.zstream; int ret; zstream->avail_in = size; zstream->next_in = data; while (zstream->avail_in > 0) { ret = deflate(zstream, Z_NO_FLUSH); if (ret != Z_OK) return -1; if (zstream->avail_out == 0) { if (s->bytestream_end - s->bytestream > IOBUF_SIZE + 100) png_write_image_data(avctx, s->buf, IOBUF_SIZE); zstream->avail_out = IOBUF_SIZE; zstream->next_out = s->buf; } } return 0; } #define PNG_LRINT(d, divisor) lrint((d) * (divisor)) #define PNG_Q2D(q, divisor) PNG_LRINT(av_q2d(q), (divisor)) #define AV_WB32_PNG_D(buf, q) AV_WB32(buf, PNG_Q2D(q, 100000)) static int png_get_chrm(enum AVColorPrimaries prim, uint8_t *buf) { const AVColorPrimariesDesc *desc = av_csp_primaries_desc_from_id(prim); if (!desc) return 0; AV_WB32_PNG_D(buf, desc->wp.x); AV_WB32_PNG_D(buf + 4, desc->wp.y); AV_WB32_PNG_D(buf + 8, desc->prim.r.x); AV_WB32_PNG_D(buf + 12, desc->prim.r.y); AV_WB32_PNG_D(buf + 16, desc->prim.g.x); AV_WB32_PNG_D(buf + 20, desc->prim.g.y); AV_WB32_PNG_D(buf + 24, desc->prim.b.x); AV_WB32_PNG_D(buf + 28, desc->prim.b.y); return 1; } static int png_get_gama(enum AVColorTransferCharacteristic trc, uint8_t *buf) { double gamma = av_csp_approximate_trc_gamma(trc); if (gamma <= 1e-6) return 0; AV_WB32(buf, PNG_LRINT(1.0 / gamma, 100000)); return 1; } static int png_write_iccp(PNGEncContext *s, const AVFrameSideData *sd) { z_stream *const zstream = &s->zstream.zstream; const AVDictionaryEntry *entry; const char *name; uint8_t *start, *buf; int ret; if (!sd || !sd->size) return 0; zstream->next_in = sd->data; zstream->avail_in = sd->size; /* write the chunk contents first */ start = s->bytestream + 8; /* make room for iCCP tag + length */ buf = start; /* profile description */ entry = av_dict_get(sd->metadata, "name", NULL, 0); name = (entry && entry->value[0]) ? entry->value : "icc"; for (int i = 0;; i++) { char c = (i == 79) ? 0 : name[i]; bytestream_put_byte(&buf, c); if (!c) break; } /* compression method and profile data */ bytestream_put_byte(&buf, 0); zstream->next_out = buf; zstream->avail_out = s->bytestream_end - buf; ret = deflate(zstream, Z_FINISH); deflateReset(zstream); if (ret != Z_STREAM_END) return AVERROR_EXTERNAL; /* rewind to the start and write the chunk header/crc */ png_write_chunk(&s->bytestream, MKTAG('i', 'C', 'C', 'P'), start, zstream->next_out - start); return 0; } static int encode_headers(AVCodecContext *avctx, const AVFrame *pict) { AVFrameSideData *side_data; PNGEncContext *s = avctx->priv_data; int ret; /* write png header */ AV_WB32(s->buf, avctx->width); AV_WB32(s->buf + 4, avctx->height); s->buf[8] = s->bit_depth; s->buf[9] = s->color_type; s->buf[10] = 0; /* compression type */ s->buf[11] = 0; /* filter type */ s->buf[12] = s->is_progressive; /* interlace type */ png_write_chunk(&s->bytestream, MKTAG('I', 'H', 'D', 'R'), s->buf, 13); /* write physical information */ if (s->dpm) { AV_WB32(s->buf, s->dpm); AV_WB32(s->buf + 4, s->dpm); s->buf[8] = 1; /* unit specifier is meter */ } else { AV_WB32(s->buf, avctx->sample_aspect_ratio.num); AV_WB32(s->buf + 4, avctx->sample_aspect_ratio.den); s->buf[8] = 0; /* unit specifier is unknown */ } png_write_chunk(&s->bytestream, MKTAG('p', 'H', 'Y', 's'), s->buf, 9); /* write stereoscopic information */ side_data = av_frame_get_side_data(pict, AV_FRAME_DATA_STEREO3D); if (side_data) { AVStereo3D *stereo3d = (AVStereo3D *)side_data->data; switch (stereo3d->type) { case AV_STEREO3D_SIDEBYSIDE: s->buf[0] = ((stereo3d->flags & AV_STEREO3D_FLAG_INVERT) == 0) ? 1 : 0; png_write_chunk(&s->bytestream, MKTAG('s', 'T', 'E', 'R'), s->buf, 1); break; case AV_STEREO3D_2D: break; default: av_log(avctx, AV_LOG_WARNING, "Only side-by-side stereo3d flag can be defined within sTER chunk\n"); break; } } side_data = av_frame_get_side_data(pict, AV_FRAME_DATA_ICC_PROFILE); if ((ret = png_write_iccp(s, side_data))) return ret; /* write colorspace information */ if (pict->color_primaries == AVCOL_PRI_BT709 && pict->color_trc == AVCOL_TRC_IEC61966_2_1) { s->buf[0] = 1; /* rendering intent, relative colorimetric by default */ png_write_chunk(&s->bytestream, MKTAG('s', 'R', 'G', 'B'), s->buf, 1); } else if (pict->color_trc != AVCOL_TRC_UNSPECIFIED && !side_data) { /* * Avoid writing cICP if the transfer is unknown. Known primaries * with unknown transfer can be handled by cHRM. * * We also avoid writing cICP if an ICC Profile is present, because * the standard requires that cICP overrides iCCP. * * These values match H.273 so no translation is needed. */ s->buf[0] = pict->color_primaries; s->buf[1] = pict->color_trc; s->buf[2] = 0; /* colorspace = RGB */ s->buf[3] = pict->color_range == AVCOL_RANGE_MPEG ? 0 : 1; png_write_chunk(&s->bytestream, MKTAG('c', 'I', 'C', 'P'), s->buf, 4); } side_data = av_frame_get_side_data(pict, AV_FRAME_DATA_CONTENT_LIGHT_LEVEL); if (side_data) { AVContentLightMetadata *clli = (AVContentLightMetadata *) side_data->data; AV_WB32(s->buf, clli->MaxCLL * 10000); AV_WB32(s->buf + 4, clli->MaxFALL * 10000); png_write_chunk(&s->bytestream, MKTAG('c', 'L', 'L', 'i'), s->buf, 8); } side_data = av_frame_get_side_data(pict, AV_FRAME_DATA_MASTERING_DISPLAY_METADATA); if (side_data) { AVMasteringDisplayMetadata *mdvc = (AVMasteringDisplayMetadata *) side_data->data; if (mdvc->has_luminance && mdvc->has_primaries) { for (int i = 0; i < 3; i++) { AV_WB16(s->buf + 2*i, PNG_Q2D(mdvc->display_primaries[i][0], 50000)); AV_WB16(s->buf + 2*i + 2, PNG_Q2D(mdvc->display_primaries[i][1], 50000)); } AV_WB16(s->buf + 12, PNG_Q2D(mdvc->white_point[0], 50000)); AV_WB16(s->buf + 14, PNG_Q2D(mdvc->white_point[1], 50000)); AV_WB32(s->buf + 16, PNG_Q2D(mdvc->max_luminance, 10000)); AV_WB32(s->buf + 20, PNG_Q2D(mdvc->min_luminance, 10000)); png_write_chunk(&s->bytestream, MKTAG('m', 'D', 'V', 'c'), s->buf, 24); } } if (png_get_chrm(pict->color_primaries, s->buf)) png_write_chunk(&s->bytestream, MKTAG('c', 'H', 'R', 'M'), s->buf, 32); if (png_get_gama(pict->color_trc, s->buf)) png_write_chunk(&s->bytestream, MKTAG('g', 'A', 'M', 'A'), s->buf, 4); if (avctx->bits_per_raw_sample > 0 && avctx->bits_per_raw_sample < s->bit_depth) { int len = ff_png_get_nb_channels(s->color_type); memset(s->buf, avctx->bits_per_raw_sample, len); png_write_chunk(&s->bytestream, MKTAG('s', 'B', 'I', 'T'), s->buf, len); } /* put the palette if needed, must be after colorspace information */ if (s->color_type == PNG_COLOR_TYPE_PALETTE) { int has_alpha, alpha, i; unsigned int v; uint32_t *palette; uint8_t *ptr, *alpha_ptr; palette = (uint32_t *)pict->data[1]; ptr = s->buf; alpha_ptr = s->buf + 256 * 3; has_alpha = 0; for (i = 0; i < 256; i++) { v = palette[i]; alpha = v >> 24; if (alpha != 0xff) has_alpha = 1; *alpha_ptr++ = alpha; bytestream_put_be24(&ptr, v); } png_write_chunk(&s->bytestream, MKTAG('P', 'L', 'T', 'E'), s->buf, 256 * 3); if (has_alpha) { png_write_chunk(&s->bytestream, MKTAG('t', 'R', 'N', 'S'), s->buf + 256 * 3, 256); } } return 0; } static int encode_frame(AVCodecContext *avctx, const AVFrame *pict) { PNGEncContext *s = avctx->priv_data; z_stream *const zstream = &s->zstream.zstream; const AVFrame *const p = pict; int y, len, ret; int row_size, pass_row_size; uint8_t *crow_buf, *crow; uint8_t *crow_base = NULL; uint8_t *progressive_buf = NULL; uint8_t *top_buf = NULL; row_size = (pict->width * s->bits_per_pixel + 7) >> 3; crow_base = av_malloc((row_size + 32) << (s->filter_type == PNG_FILTER_VALUE_MIXED)); if (!crow_base) { ret = AVERROR(ENOMEM); goto the_end; } // pixel data should be aligned, but there's a control byte before it crow_buf = crow_base + 15; if (s->is_progressive) { progressive_buf = av_malloc(row_size + 1); top_buf = av_malloc(row_size + 1); if (!progressive_buf || !top_buf) { ret = AVERROR(ENOMEM); goto the_end; } } /* put each row */ zstream->avail_out = IOBUF_SIZE; zstream->next_out = s->buf; if (s->is_progressive) { int pass; for (pass = 0; pass < NB_PASSES; pass++) { /* NOTE: a pass is completely omitted if no pixels would be * output */ pass_row_size = ff_png_pass_row_size(pass, s->bits_per_pixel, pict->width); if (pass_row_size > 0) { uint8_t *top = NULL; for (y = 0; y < pict->height; y++) if ((ff_png_pass_ymask[pass] << (y & 7)) & 0x80) { const uint8_t *ptr = p->data[0] + y * p->linesize[0]; FFSWAP(uint8_t *, progressive_buf, top_buf); png_get_interlaced_row(progressive_buf, pass_row_size, s->bits_per_pixel, pass, ptr, pict->width); crow = png_choose_filter(s, crow_buf, progressive_buf, top, pass_row_size, s->bits_per_pixel >> 3); png_write_row(avctx, crow, pass_row_size + 1); top = progressive_buf; } } } } else { const uint8_t *top = NULL; for (y = 0; y < pict->height; y++) { const uint8_t *ptr = p->data[0] + y * p->linesize[0]; crow = png_choose_filter(s, crow_buf, ptr, top, row_size, s->bits_per_pixel >> 3); png_write_row(avctx, crow, row_size + 1); top = ptr; } } /* compress last bytes */ for (;;) { ret = deflate(zstream, Z_FINISH); if (ret == Z_OK || ret == Z_STREAM_END) { len = IOBUF_SIZE - zstream->avail_out; if (len > 0 && s->bytestream_end - s->bytestream > len + 100) { png_write_image_data(avctx, s->buf, len); } zstream->avail_out = IOBUF_SIZE; zstream->next_out = s->buf; if (ret == Z_STREAM_END) break; } else { ret = -1; goto the_end; } } ret = 0; the_end: av_freep(&crow_base); av_freep(&progressive_buf); av_freep(&top_buf); deflateReset(zstream); return ret; } static int add_icc_profile_size(AVCodecContext *avctx, const AVFrame *pict, uint64_t *max_packet_size) { PNGEncContext *s = avctx->priv_data; const AVFrameSideData *sd; const int hdr_size = 128; uint64_t new_pkt_size; uLong bound; if (!pict) return 0; sd = av_frame_get_side_data(pict, AV_FRAME_DATA_ICC_PROFILE); if (!sd || !sd->size) return 0; if (sd->size != (uLong) sd->size) return AVERROR_INVALIDDATA; bound = deflateBound(&s->zstream.zstream, sd->size); if (bound > INT32_MAX - hdr_size) return AVERROR_INVALIDDATA; new_pkt_size = *max_packet_size + bound + hdr_size; if (new_pkt_size < *max_packet_size) return AVERROR_INVALIDDATA; *max_packet_size = new_pkt_size; return 0; } static int encode_png(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *pict, int *got_packet) { PNGEncContext *s = avctx->priv_data; int ret; int enc_row_size; uint64_t max_packet_size; enc_row_size = deflateBound(&s->zstream.zstream, (avctx->width * s->bits_per_pixel + 7) >> 3); max_packet_size = FF_INPUT_BUFFER_MIN_SIZE + // headers avctx->height * ( enc_row_size + 12 * (((int64_t)enc_row_size + IOBUF_SIZE - 1) / IOBUF_SIZE) // IDAT * ceil(enc_row_size / IOBUF_SIZE) ); if ((ret = add_icc_profile_size(avctx, pict, &max_packet_size))) return ret; ret = ff_alloc_packet(avctx, pkt, max_packet_size); if (ret < 0) return ret; s->bytestream_start = s->bytestream = pkt->data; s->bytestream_end = pkt->data + pkt->size; AV_WB64(s->bytestream, PNGSIG); s->bytestream += 8; ret = encode_headers(avctx, pict); if (ret < 0) return ret; ret = encode_frame(avctx, pict); if (ret < 0) return ret; png_write_chunk(&s->bytestream, MKTAG('I', 'E', 'N', 'D'), NULL, 0); pkt->size = s->bytestream - s->bytestream_start; pkt->flags |= AV_PKT_FLAG_KEY; *got_packet = 1; return 0; } static int apng_do_inverse_blend(AVFrame *output, const AVFrame *input, APNGFctlChunk *fctl_chunk, uint8_t bpp) { // output: background, input: foreground // output the image such that when blended with the background, will produce the foreground unsigned int x, y; unsigned int leftmost_x = input->width; unsigned int rightmost_x = 0; unsigned int topmost_y = input->height; unsigned int bottommost_y = 0; const uint8_t *input_data = input->data[0]; uint8_t *output_data = output->data[0]; ptrdiff_t input_linesize = input->linesize[0]; ptrdiff_t output_linesize = output->linesize[0]; // Find bounding box of changes for (y = 0; y < input->height; ++y) { for (x = 0; x < input->width; ++x) { if (!memcmp(input_data + bpp * x, output_data + bpp * x, bpp)) continue; if (x < leftmost_x) leftmost_x = x; if (x >= rightmost_x) rightmost_x = x + 1; if (y < topmost_y) topmost_y = y; if (y >= bottommost_y) bottommost_y = y + 1; } input_data += input_linesize; output_data += output_linesize; } if (leftmost_x == input->width && rightmost_x == 0) { // Empty frame // APNG does not support empty frames, so we make it a 1x1 frame leftmost_x = topmost_y = 0; rightmost_x = bottommost_y = 1; } // Do actual inverse blending if (fctl_chunk->blend_op == APNG_BLEND_OP_SOURCE) { output_data = output->data[0]; for (y = topmost_y; y < bottommost_y; ++y) { memcpy(output_data, input->data[0] + input_linesize * y + bpp * leftmost_x, bpp * (rightmost_x - leftmost_x)); output_data += output_linesize; } } else { // APNG_BLEND_OP_OVER size_t transparent_palette_index; uint32_t *palette; switch (input->format) { case AV_PIX_FMT_RGBA64BE: case AV_PIX_FMT_YA16BE: case AV_PIX_FMT_RGBA: case AV_PIX_FMT_GRAY8A: break; case AV_PIX_FMT_PAL8: palette = (uint32_t*)input->data[1]; for (transparent_palette_index = 0; transparent_palette_index < 256; ++transparent_palette_index) if (palette[transparent_palette_index] >> 24 == 0) break; break; default: // No alpha, so blending not possible return -1; } for (y = topmost_y; y < bottommost_y; ++y) { const uint8_t *foreground = input->data[0] + input_linesize * y + bpp * leftmost_x; uint8_t *background = output->data[0] + output_linesize * y + bpp * leftmost_x; output_data = output->data[0] + output_linesize * (y - topmost_y); for (x = leftmost_x; x < rightmost_x; ++x, foreground += bpp, background += bpp, output_data += bpp) { if (!memcmp(foreground, background, bpp)) { if (input->format == AV_PIX_FMT_PAL8) { if (transparent_palette_index == 256) { // Need fully transparent colour, but none exists return -1; } *output_data = transparent_palette_index; } else { memset(output_data, 0, bpp); } continue; } // Check for special alpha values, since full inverse // alpha-on-alpha blending is rarely possible, and when // possible, doesn't compress much better than // APNG_BLEND_OP_SOURCE blending switch (input->format) { case AV_PIX_FMT_RGBA64BE: if (((uint16_t*)foreground)[3] == 0xffff || ((uint16_t*)background)[3] == 0) break; return -1; case AV_PIX_FMT_YA16BE: if (((uint16_t*)foreground)[1] == 0xffff || ((uint16_t*)background)[1] == 0) break; return -1; case AV_PIX_FMT_RGBA: if (foreground[3] == 0xff || background[3] == 0) break; return -1; case AV_PIX_FMT_GRAY8A: if (foreground[1] == 0xff || background[1] == 0) break; return -1; case AV_PIX_FMT_PAL8: if (palette[*foreground] >> 24 == 0xff || palette[*background] >> 24 == 0) break; return -1; } memmove(output_data, foreground, bpp); } } } output->width = rightmost_x - leftmost_x; output->height = bottommost_y - topmost_y; fctl_chunk->width = output->width; fctl_chunk->height = output->height; fctl_chunk->x_offset = leftmost_x; fctl_chunk->y_offset = topmost_y; return 0; } static int apng_encode_frame(AVCodecContext *avctx, const AVFrame *pict, APNGFctlChunk *best_fctl_chunk, APNGFctlChunk *best_last_fctl_chunk) { PNGEncContext *s = avctx->priv_data; int ret; unsigned int y; AVFrame* diffFrame; uint8_t bpp = (s->bits_per_pixel + 7) >> 3; uint8_t *original_bytestream, *original_bytestream_end; uint8_t *temp_bytestream = 0, *temp_bytestream_end; uint32_t best_sequence_number; uint8_t *best_bytestream; size_t best_bytestream_size = SIZE_MAX; APNGFctlChunk last_fctl_chunk = *best_last_fctl_chunk; APNGFctlChunk fctl_chunk = *best_fctl_chunk; if (avctx->frame_num == 0) { best_fctl_chunk->width = pict->width; best_fctl_chunk->height = pict->height; best_fctl_chunk->x_offset = 0; best_fctl_chunk->y_offset = 0; best_fctl_chunk->blend_op = APNG_BLEND_OP_SOURCE; return encode_frame(avctx, pict); } diffFrame = av_frame_alloc(); if (!diffFrame) return AVERROR(ENOMEM); diffFrame->format = pict->format; diffFrame->width = pict->width; diffFrame->height = pict->height; if ((ret = av_frame_get_buffer(diffFrame, 0)) < 0) goto fail; original_bytestream = s->bytestream; original_bytestream_end = s->bytestream_end; temp_bytestream = av_malloc(original_bytestream_end - original_bytestream); if (!temp_bytestream) { ret = AVERROR(ENOMEM); goto fail; } temp_bytestream_end = temp_bytestream + (original_bytestream_end - original_bytestream); for (last_fctl_chunk.dispose_op = 0; last_fctl_chunk.dispose_op < 3; ++last_fctl_chunk.dispose_op) { // 0: APNG_DISPOSE_OP_NONE // 1: APNG_DISPOSE_OP_BACKGROUND // 2: APNG_DISPOSE_OP_PREVIOUS for (fctl_chunk.blend_op = 0; fctl_chunk.blend_op < 2; ++fctl_chunk.blend_op) { // 0: APNG_BLEND_OP_SOURCE // 1: APNG_BLEND_OP_OVER uint32_t original_sequence_number = s->sequence_number, sequence_number; uint8_t *bytestream_start = s->bytestream; size_t bytestream_size; // Do disposal if (last_fctl_chunk.dispose_op != APNG_DISPOSE_OP_PREVIOUS) { diffFrame->width = pict->width; diffFrame->height = pict->height; ret = av_frame_copy(diffFrame, s->last_frame); if (ret < 0) goto fail; if (last_fctl_chunk.dispose_op == APNG_DISPOSE_OP_BACKGROUND) { for (y = last_fctl_chunk.y_offset; y < last_fctl_chunk.y_offset + last_fctl_chunk.height; ++y) { size_t row_start = diffFrame->linesize[0] * y + bpp * last_fctl_chunk.x_offset; memset(diffFrame->data[0] + row_start, 0, bpp * last_fctl_chunk.width); } } } else { if (!s->prev_frame) continue; diffFrame->width = pict->width; diffFrame->height = pict->height; ret = av_frame_copy(diffFrame, s->prev_frame); if (ret < 0) goto fail; } // Do inverse blending if (apng_do_inverse_blend(diffFrame, pict, &fctl_chunk, bpp) < 0) continue; // Do encoding ret = encode_frame(avctx, diffFrame); sequence_number = s->sequence_number; s->sequence_number = original_sequence_number; bytestream_size = s->bytestream - bytestream_start; s->bytestream = bytestream_start; if (ret < 0) goto fail; if (bytestream_size < best_bytestream_size) { *best_fctl_chunk = fctl_chunk; *best_last_fctl_chunk = last_fctl_chunk; best_sequence_number = sequence_number; best_bytestream = s->bytestream; best_bytestream_size = bytestream_size; if (best_bytestream == original_bytestream) { s->bytestream = temp_bytestream; s->bytestream_end = temp_bytestream_end; } else { s->bytestream = original_bytestream; s->bytestream_end = original_bytestream_end; } } } } s->sequence_number = best_sequence_number; s->bytestream = original_bytestream + best_bytestream_size; s->bytestream_end = original_bytestream_end; if (best_bytestream != original_bytestream) memcpy(original_bytestream, best_bytestream, best_bytestream_size); ret = 0; fail: av_freep(&temp_bytestream); av_frame_free(&diffFrame); return ret; } static int encode_apng(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *pict, int *got_packet) { PNGEncContext *s = avctx->priv_data; int ret; int enc_row_size; uint64_t max_packet_size; APNGFctlChunk fctl_chunk = {0}; if (pict && s->color_type == PNG_COLOR_TYPE_PALETTE) { uint32_t checksum = ~av_crc(av_crc_get_table(AV_CRC_32_IEEE_LE), ~0U, pict->data[1], 256 * sizeof(uint32_t)); if (avctx->frame_num == 0) { s->palette_checksum = checksum; } else if (checksum != s->palette_checksum) { av_log(avctx, AV_LOG_ERROR, "Input contains more than one unique palette. APNG does not support multiple palettes.\n"); return -1; } } enc_row_size = deflateBound(&s->zstream.zstream, (avctx->width * s->bits_per_pixel + 7) >> 3); max_packet_size = FF_INPUT_BUFFER_MIN_SIZE + // headers avctx->height * ( enc_row_size + (4 + 12) * (((int64_t)enc_row_size + IOBUF_SIZE - 1) / IOBUF_SIZE) // fdAT * ceil(enc_row_size / IOBUF_SIZE) ); if ((ret = add_icc_profile_size(avctx, pict, &max_packet_size))) return ret; if (max_packet_size > INT_MAX) return AVERROR(ENOMEM); if (avctx->frame_num == 0) { if (!pict) return AVERROR(EINVAL); s->bytestream = s->extra_data = av_malloc(FF_INPUT_BUFFER_MIN_SIZE); if (!s->extra_data) return AVERROR(ENOMEM); ret = encode_headers(avctx, pict); if (ret < 0) return ret; s->extra_data_size = s->bytestream - s->extra_data; s->last_frame_packet = av_malloc(max_packet_size); if (!s->last_frame_packet) return AVERROR(ENOMEM); } else if (s->last_frame) { ret = ff_get_encode_buffer(avctx, pkt, s->last_frame_packet_size, 0); if (ret < 0) return ret; memcpy(pkt->data, s->last_frame_packet, s->last_frame_packet_size); pkt->pts = s->last_frame->pts; pkt->duration = s->last_frame->duration; ret = ff_encode_reordered_opaque(avctx, pkt, s->last_frame); if (ret < 0) return ret; } if (pict) { s->bytestream_start = s->bytestream = s->last_frame_packet; s->bytestream_end = s->bytestream + max_packet_size; // We're encoding the frame first, so we have to do a bit of shuffling around // to have the image data write to the correct place in the buffer fctl_chunk.sequence_number = s->sequence_number; ++s->sequence_number; s->bytestream += APNG_FCTL_CHUNK_SIZE + 12; ret = apng_encode_frame(avctx, pict, &fctl_chunk, &s->last_frame_fctl); if (ret < 0) return ret; fctl_chunk.delay_num = 0; // delay filled in during muxing fctl_chunk.delay_den = 0; } else { s->last_frame_fctl.dispose_op = APNG_DISPOSE_OP_NONE; } if (s->last_frame) { uint8_t* last_fctl_chunk_start = pkt->data; uint8_t buf[APNG_FCTL_CHUNK_SIZE]; if (!s->extra_data_updated) { uint8_t *side_data = av_packet_new_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA, s->extra_data_size); if (!side_data) return AVERROR(ENOMEM); memcpy(side_data, s->extra_data, s->extra_data_size); s->extra_data_updated = 1; } AV_WB32(buf + 0, s->last_frame_fctl.sequence_number); AV_WB32(buf + 4, s->last_frame_fctl.width); AV_WB32(buf + 8, s->last_frame_fctl.height); AV_WB32(buf + 12, s->last_frame_fctl.x_offset); AV_WB32(buf + 16, s->last_frame_fctl.y_offset); AV_WB16(buf + 20, s->last_frame_fctl.delay_num); AV_WB16(buf + 22, s->last_frame_fctl.delay_den); buf[24] = s->last_frame_fctl.dispose_op; buf[25] = s->last_frame_fctl.blend_op; png_write_chunk(&last_fctl_chunk_start, MKTAG('f', 'c', 'T', 'L'), buf, sizeof(buf)); *got_packet = 1; } if (pict) { if (!s->last_frame) { s->last_frame = av_frame_alloc(); if (!s->last_frame) return AVERROR(ENOMEM); } else if (s->last_frame_fctl.dispose_op != APNG_DISPOSE_OP_PREVIOUS) { if (!s->prev_frame) { s->prev_frame = av_frame_alloc(); if (!s->prev_frame) return AVERROR(ENOMEM); s->prev_frame->format = pict->format; s->prev_frame->width = pict->width; s->prev_frame->height = pict->height; if ((ret = av_frame_get_buffer(s->prev_frame, 0)) < 0) return ret; } // Do disposal, but not blending av_frame_copy(s->prev_frame, s->last_frame); if (s->last_frame_fctl.dispose_op == APNG_DISPOSE_OP_BACKGROUND) { uint32_t y; uint8_t bpp = (s->bits_per_pixel + 7) >> 3; for (y = s->last_frame_fctl.y_offset; y < s->last_frame_fctl.y_offset + s->last_frame_fctl.height; ++y) { size_t row_start = s->prev_frame->linesize[0] * y + bpp * s->last_frame_fctl.x_offset; memset(s->prev_frame->data[0] + row_start, 0, bpp * s->last_frame_fctl.width); } } } ret = av_frame_replace(s->last_frame, pict); if (ret < 0) return ret; s->last_frame_fctl = fctl_chunk; s->last_frame_packet_size = s->bytestream - s->bytestream_start; } else { av_frame_free(&s->last_frame); } return 0; } static av_cold int png_enc_init(AVCodecContext *avctx) { PNGEncContext *s = avctx->priv_data; int compression_level; switch (avctx->pix_fmt) { case AV_PIX_FMT_RGBA: avctx->bits_per_coded_sample = 32; break; case AV_PIX_FMT_RGB24: avctx->bits_per_coded_sample = 24; break; case AV_PIX_FMT_GRAY8: avctx->bits_per_coded_sample = 0x28; break; case AV_PIX_FMT_MONOBLACK: avctx->bits_per_coded_sample = 1; break; case AV_PIX_FMT_PAL8: avctx->bits_per_coded_sample = 8; } ff_llvidencdsp_init(&s->llvidencdsp); if (avctx->pix_fmt == AV_PIX_FMT_MONOBLACK) s->filter_type = PNG_FILTER_VALUE_NONE; if (s->dpi && s->dpm) { av_log(avctx, AV_LOG_ERROR, "Only one of 'dpi' or 'dpm' options should be set\n"); return AVERROR(EINVAL); } else if (s->dpi) { s->dpm = s->dpi * 10000 / 254; } s->is_progressive = !!(avctx->flags & AV_CODEC_FLAG_INTERLACED_DCT); switch (avctx->pix_fmt) { case AV_PIX_FMT_RGBA64BE: s->bit_depth = 16; s->color_type = PNG_COLOR_TYPE_RGB_ALPHA; break; case AV_PIX_FMT_RGB48BE: s->bit_depth = 16; s->color_type = PNG_COLOR_TYPE_RGB; break; case AV_PIX_FMT_RGBA: s->bit_depth = 8; s->color_type = PNG_COLOR_TYPE_RGB_ALPHA; break; case AV_PIX_FMT_RGB24: s->bit_depth = 8; s->color_type = PNG_COLOR_TYPE_RGB; break; case AV_PIX_FMT_GRAY16BE: s->bit_depth = 16; s->color_type = PNG_COLOR_TYPE_GRAY; break; case AV_PIX_FMT_GRAY8: s->bit_depth = 8; s->color_type = PNG_COLOR_TYPE_GRAY; break; case AV_PIX_FMT_GRAY8A: s->bit_depth = 8; s->color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break; case AV_PIX_FMT_YA16BE: s->bit_depth = 16; s->color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break; case AV_PIX_FMT_MONOBLACK: s->bit_depth = 1; s->color_type = PNG_COLOR_TYPE_GRAY; break; case AV_PIX_FMT_PAL8: s->bit_depth = 8; s->color_type = PNG_COLOR_TYPE_PALETTE; break; default: return -1; } s->bits_per_pixel = ff_png_get_nb_channels(s->color_type) * s->bit_depth; compression_level = avctx->compression_level == FF_COMPRESSION_DEFAULT ? Z_DEFAULT_COMPRESSION : av_clip(avctx->compression_level, 0, 9); return ff_deflate_init(&s->zstream, compression_level, avctx); } static av_cold int png_enc_close(AVCodecContext *avctx) { PNGEncContext *s = avctx->priv_data; ff_deflate_end(&s->zstream); av_frame_free(&s->last_frame); av_frame_free(&s->prev_frame); av_freep(&s->last_frame_packet); av_freep(&s->extra_data); s->extra_data_size = 0; return 0; } #define OFFSET(x) offsetof(PNGEncContext, x) #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM static const AVOption options[] = { {"dpi", "Set image resolution (in dots per inch)", OFFSET(dpi), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 0x10000, VE}, {"dpm", "Set image resolution (in dots per meter)", OFFSET(dpm), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 0x10000, VE}, { "pred", "Prediction method", OFFSET(filter_type), AV_OPT_TYPE_INT, { .i64 = PNG_FILTER_VALUE_NONE }, PNG_FILTER_VALUE_NONE, PNG_FILTER_VALUE_MIXED, VE, .unit = "pred" }, { "none", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = PNG_FILTER_VALUE_NONE }, INT_MIN, INT_MAX, VE, .unit = "pred" }, { "sub", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = PNG_FILTER_VALUE_SUB }, INT_MIN, INT_MAX, VE, .unit = "pred" }, { "up", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = PNG_FILTER_VALUE_UP }, INT_MIN, INT_MAX, VE, .unit = "pred" }, { "avg", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = PNG_FILTER_VALUE_AVG }, INT_MIN, INT_MAX, VE, .unit = "pred" }, { "paeth", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = PNG_FILTER_VALUE_PAETH }, INT_MIN, INT_MAX, VE, .unit = "pred" }, { "mixed", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = PNG_FILTER_VALUE_MIXED }, INT_MIN, INT_MAX, VE, .unit = "pred" }, { NULL}, }; static const AVClass pngenc_class = { .class_name = "(A)PNG encoder", .item_name = av_default_item_name, .option = options, .version = LIBAVUTIL_VERSION_INT, }; const FFCodec ff_png_encoder = { .p.name = "png", CODEC_LONG_NAME("PNG (Portable Network Graphics) image"), .p.type = AVMEDIA_TYPE_VIDEO, .p.id = AV_CODEC_ID_PNG, .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE, .priv_data_size = sizeof(PNGEncContext), .init = png_enc_init, .close = png_enc_close, FF_CODEC_ENCODE_CB(encode_png), .p.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_RGB24, AV_PIX_FMT_RGBA, AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGBA64BE, AV_PIX_FMT_PAL8, AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY8A, AV_PIX_FMT_GRAY16BE, AV_PIX_FMT_YA16BE, AV_PIX_FMT_MONOBLACK, AV_PIX_FMT_NONE }, .p.priv_class = &pngenc_class, .caps_internal = FF_CODEC_CAP_ICC_PROFILES, }; const FFCodec ff_apng_encoder = { .p.name = "apng", CODEC_LONG_NAME("APNG (Animated Portable Network Graphics) image"), .p.type = AVMEDIA_TYPE_VIDEO, .p.id = AV_CODEC_ID_APNG, .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DELAY | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE, .priv_data_size = sizeof(PNGEncContext), .init = png_enc_init, .close = png_enc_close, FF_CODEC_ENCODE_CB(encode_apng), .p.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_RGB24, AV_PIX_FMT_RGBA, AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGBA64BE, AV_PIX_FMT_PAL8, AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY8A, AV_PIX_FMT_GRAY16BE, AV_PIX_FMT_YA16BE, AV_PIX_FMT_NONE }, .p.priv_class = &pngenc_class, .caps_internal = FF_CODEC_CAP_ICC_PROFILES, };