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- /*
- * Copyright (c) 1990 James Ashton - Sydney University
- * Copyright (c) 2012 Stefano Sabatini
- *
- * 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
- * X-Face encoder, based on libcompface, by James Ashton.
- */
-
- #include "xface.h"
- #include "avcodec.h"
- #include "internal.h"
-
- typedef struct XFaceContext {
- AVClass *class;
- uint8_t bitmap[XFACE_PIXELS]; ///< image used internally for decoding
- int max_line_len; ///< max line length for compressed data
- int set_header; ///< set X-Face header in the output
- } XFaceContext;
-
- static int all_same(char *bitmap, int w, int h)
- {
- char val, *row;
- int x;
-
- val = *bitmap;
- while (h--) {
- row = bitmap;
- x = w;
- while (x--)
- if (*(row++) != val)
- return 0;
- bitmap += XFACE_WIDTH;
- }
- return 1;
- }
-
- static int all_black(char *bitmap, int w, int h)
- {
- if (w > 3) {
- w /= 2;
- h /= 2;
- return (all_black(bitmap, w, h) && all_black(bitmap + w, w, h) &&
- all_black(bitmap + XFACE_WIDTH * h, w, h) &&
- all_black(bitmap + XFACE_WIDTH * h + w, w, h));
- } else {
- /* at least one pixel in the 2x2 grid is non-zero */
- return *bitmap || *(bitmap + 1) ||
- *(bitmap + XFACE_WIDTH) || *(bitmap + XFACE_WIDTH + 1);
- }
- }
-
- static int all_white(char *bitmap, int w, int h)
- {
- return *bitmap == 0 && all_same(bitmap, w, h);
- }
-
- typedef struct {
- const ProbRange *prob_ranges[XFACE_PIXELS*2];
- int prob_ranges_idx;
- } ProbRangesQueue;
-
- static inline int pq_push(ProbRangesQueue *pq, const ProbRange *p)
- {
- if (pq->prob_ranges_idx >= XFACE_PIXELS * 2 - 1)
- return -1;
- pq->prob_ranges[pq->prob_ranges_idx++] = p;
- return 0;
- }
-
- static void push_greys(ProbRangesQueue *pq, char *bitmap, int w, int h)
- {
- if (w > 3) {
- w /= 2;
- h /= 2;
- push_greys(pq, bitmap, w, h);
- push_greys(pq, bitmap + w, w, h);
- push_greys(pq, bitmap + XFACE_WIDTH * h, w, h);
- push_greys(pq, bitmap + XFACE_WIDTH * h + w, w, h);
- } else {
- const ProbRange *p = ff_xface_probranges_2x2 +
- *bitmap +
- 2 * *(bitmap + 1) +
- 4 * *(bitmap + XFACE_WIDTH) +
- 8 * *(bitmap + XFACE_WIDTH + 1);
- pq_push(pq, p);
- }
- }
-
- static void encode_block(char *bitmap, int w, int h, int level, ProbRangesQueue *pq)
- {
- if (all_white(bitmap, w, h)) {
- pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_WHITE]);
- } else if (all_black(bitmap, w, h)) {
- pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_BLACK]);
- push_greys(pq, bitmap, w, h);
- } else {
- pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_GREY]);
- w /= 2;
- h /= 2;
- level++;
- encode_block(bitmap, w, h, level, pq);
- encode_block(bitmap + w, w, h, level, pq);
- encode_block(bitmap + h * XFACE_WIDTH, w, h, level, pq);
- encode_block(bitmap + w + h * XFACE_WIDTH, w, h, level, pq);
- }
- }
-
- static av_cold int xface_encode_init(AVCodecContext *avctx)
- {
- avctx->coded_frame = avcodec_alloc_frame();
- if (!avctx->coded_frame)
- return AVERROR(ENOMEM);
- avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
-
- return 0;
- }
-
- static void push_integer(BigInt *b, const ProbRange *prange)
- {
- uint8_t r;
-
- ff_big_div(b, prange->range, &r);
- ff_big_mul(b, 0);
- ff_big_add(b, r + prange->offset);
- }
-
- static int xface_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
- const AVFrame *frame, int *got_packet)
- {
- XFaceContext *xface = avctx->priv_data;
- ProbRangesQueue pq = {{ 0 }, 0};
- uint8_t bitmap_copy[XFACE_PIXELS];
- BigInt b = {0};
- int i, j, k, ret = 0;
- const uint8_t *buf;
- uint8_t *p;
- char intbuf[XFACE_MAX_DIGITS];
-
- if (avctx->width || avctx->height) {
- if (avctx->width != XFACE_WIDTH || avctx->height != XFACE_HEIGHT) {
- av_log(avctx, AV_LOG_ERROR,
- "Size value %dx%d not supported, only accepts a size of %dx%d\n",
- avctx->width, avctx->height, XFACE_WIDTH, XFACE_HEIGHT);
- return AVERROR(EINVAL);
- }
- }
- avctx->width = XFACE_WIDTH;
- avctx->height = XFACE_HEIGHT;
-
- /* convert image from MONOWHITE to 1=black 0=white bitmap */
- buf = frame->data[0];
- for (i = 0, j = 0; i < XFACE_PIXELS; ) {
- for (k = 0; k < 8; k++)
- xface->bitmap[i++] = (buf[j]>>(7-k))&1;
- if (++j == XFACE_WIDTH/8) {
- buf += frame->linesize[0];
- j = 0;
- }
- }
-
- /* create a copy of bitmap */
- memcpy(bitmap_copy, xface->bitmap, XFACE_PIXELS);
- ff_xface_generate_face(xface->bitmap, bitmap_copy);
-
- encode_block(xface->bitmap, 16, 16, 0, &pq);
- encode_block(xface->bitmap + 16, 16, 16, 0, &pq);
- encode_block(xface->bitmap + 32, 16, 16, 0, &pq);
- encode_block(xface->bitmap + XFACE_WIDTH * 16, 16, 16, 0, &pq);
- encode_block(xface->bitmap + XFACE_WIDTH * 16 + 16, 16, 16, 0, &pq);
- encode_block(xface->bitmap + XFACE_WIDTH * 16 + 32, 16, 16, 0, &pq);
- encode_block(xface->bitmap + XFACE_WIDTH * 32, 16, 16, 0, &pq);
- encode_block(xface->bitmap + XFACE_WIDTH * 32 + 16, 16, 16, 0, &pq);
- encode_block(xface->bitmap + XFACE_WIDTH * 32 + 32, 16, 16, 0, &pq);
-
- while (pq.prob_ranges_idx > 0)
- push_integer(&b, pq.prob_ranges[--pq.prob_ranges_idx]);
-
- /* write the inverted big integer in b to intbuf */
- i = 0;
- while (b.nb_words) {
- uint8_t r;
- ff_big_div(&b, XFACE_PRINTS, &r);
- intbuf[i++] = r + XFACE_FIRST_PRINT;
- }
-
- if ((ret = ff_alloc_packet2(avctx, pkt, i+2)) < 0)
- return ret;
-
- /* revert the number, and close the buffer */
- p = pkt->data;
- while (--i >= 0)
- *(p++) = intbuf[i];
- *(p++) = '\n';
- *(p++) = 0;
-
- pkt->flags |= AV_PKT_FLAG_KEY;
- *got_packet = 1;
-
- return 0;
- }
-
- static av_cold int xface_encode_close(AVCodecContext *avctx)
- {
- av_freep(&avctx->coded_frame);
-
- return 0;
- }
-
- AVCodec ff_xface_encoder = {
- .name = "xface",
- .type = AVMEDIA_TYPE_VIDEO,
- .id = AV_CODEC_ID_XFACE,
- .priv_data_size = sizeof(XFaceContext),
- .init = xface_encode_init,
- .close = xface_encode_close,
- .encode2 = xface_encode_frame,
- .pix_fmts = (const enum PixelFormat[]) { AV_PIX_FMT_MONOWHITE, AV_PIX_FMT_NONE },
- .long_name = NULL_IF_CONFIG_SMALL("X-face image"),
- };
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