On Wed, Sep 21, 2011 at 03:42:38AM +0200, Maxim wrote: > Hi crews, > > Yes, it's no mistake! What you see is just another code implementing > ProRes decoder. > > Now I'm going to explain that confusion. > Writing a ProRes compatible decoder began as team project in 2010. > During this period, I created an internal documentation on the coding > algorithm (entropy coding, slicing and inverse transform); a part of > this doc has been published at > > http://wiki.multimedia.cx/index.php?title=Apple_ProRes&action=history > > already in 2010 (see my nickname "Maxpol" for a proof), but not to much > to avoid an implementation by someone else. > > Later I wrote a working decoder. Due to the lack for interlaced frames > it was incomplete, but it could handle the most of samples available. > > Further I shared my docs and code with another developer, whose name I > don't want to mention here. He wrote his own code, heavily based on my work. > > The team suffered from poor communication and political intrigues...
It's funny how you call money here... > A few days ago that other developer has submitted his decoder > anonymously. I feel that the code, containing a significant part of my > work, was released without proper credit. Yes, we've suspected that much. > Therefore I decided to post my code as well (without any parts written > by the other guy though). Hereby I claim copyright on several parts of > the ProRes decoder (vlc, headers and slice decoding), because due to my > hard work it has reached its final form. > > My code may be of particular interest because of: > - compatible license (LGPL) > - a full description of the codec (especially its headers and encoding > algorithms) I'm going to make publicitly available soon Isn't it mostly in the wiki already? > - maintainership by a real person instead of an anonymous one > > Therefore I let you, crews, to make a final decision about all that... > > Best regards > Maxim Poliakovski > And here's a quick review (and it's really nice to see this decoder at last). > /* > * Apple ProRes compatible decoder > * > * Copyright (c) 2010-2011 Maxim Poliakovski > * > * This file is part of FFmpeg. Libav please, FFmpeg has its own decoder. > * 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 libavcodec/proresdec.c > * This is a decoder for Apple ProRes 422 SD/HQ/LT/Proxy and ProRes 4444. > * It is used for storing and editing high definition video data in Apple's > Final Cut Pro. > * For a detailed description click here: > http://wiki.multimedia.cx/index.php?title=Apple_ProRes > */ > > #define A32_BITSTREAM_READER // some ProRes vlc codes require up to 28 bits > to be read at once > > #include "avcodec.h" > #include "get_bits.h" > #include "dsputil.h" > #include "libavutil/mathematics.h" > > #define BITS_PER_SAMPLE 10 ///< output precision of that decoder > #define BIAS (1 << (BITS_PER_SAMPLE - 1)) ///< bias value for converting > signed pixels into unsigned ones > #define CLIP_MIN (1 << (BITS_PER_SAMPLE - 8)) ///< minimum value for clipping > resulting pixels > #define CLIP_MAX (1 << BITS_PER_SAMPLE) - CLIP_MIN - 1 ///< maximum value for > clipping resulting pixels it would look better with proper vertical alignment > typedef struct { > DSPContext dsp; > AVFrame picture; > ScanTable scantable; > int scantable_type; ///< -1 = uninitialized, 0 = progressive, 1/2 > = interlaced > > int frame_type; ///< 0 = progressive, 1 = top-field first, 2 > = bottom-field first > int pic_format; ///< 2 = 422, 3 = 444 > uint8_t qmat_luma[64]; ///< dequantization matrix for luma > uint8_t qmat_chroma[64]; ///< dequantization matrix for chroma > int qmat_changed; ///< 1 - global quantization matrices changed > int prev_slice_sf; ///< scalefactor of the previous decoded slice > DECLARE_ALIGNED(16, int16_t, qmat_luma_scaled[64]); > DECLARE_ALIGNED(16, int16_t, qmat_chroma_scaled[64]); > int total_slices; ///< total number of slices in a picture > const uint8_t **slice_data_index; ///< array of pointers to the data of > each slice > int chroma_factor; > int mb_chroma_factor; > int num_chroma_blocks; ///< number of chrominance blocks in a > macroblock > int num_x_slices; > int num_y_slices; > int slice_width_factor; > int slice_height_factor; > int num_x_mbs; > int num_y_mbs; > } ProresContext; > > > static const uint8_t progressive_scan[64] = { > 0, 1, 8, 9, 2, 3, 10, 11, > 16, 17, 24, 25, 18, 19, 26, 27, > 4, 5, 12, 20, 13, 6, 7, 14, > 21, 28, 29, 22, 15, 23, 30, 31, > 32, 33, 40, 48, 41, 34, 35, 42, > 49, 56, 57, 50, 43, 36, 37, 44, > 51, 58, 59, 52, 45, 38, 39, 46, > 53, 60, 61, 54, 47, 55, 62, 63 > }; > > static const uint8_t interlaced_scan[64] = { > 0, 8, 1, 9, 16, 24, 17, 25, > 2, 10, 3, 11, 18, 26, 19, 27, > 32, 40, 33, 34, 41, 48, 56, 49, > 42, 35, 43, 50, 57, 58, 51, 59, > 4, 12, 5, 6, 13, 20, 28, 21, > 14, 7, 15, 22, 29, 36, 44, 37, > 30, 23, 31, 38, 45, 52, 60, 53, > 46, 39, 47, 54, 61, 62, 55, 63 > }; > > > /** > * ProRes decoder initializations. > */ > static av_cold int decode_init(AVCodecContext * avctx) > { > ProresContext *ctx = avctx->priv_data; > > ctx->total_slices = 0; > ctx->slice_data_index = 0; > > avctx->pix_fmt = PIX_FMT_YUV422P10; // set default pixel format > > avctx->bits_per_raw_sample = BITS_PER_SAMPLE; > dsputil_init(&ctx->dsp, avctx); > > avctx->coded_frame = &ctx->picture; > avcodec_get_frame_defaults(&ctx->picture); > ctx->picture.type = AV_PICTURE_TYPE_I; > ctx->picture.key_frame = 1; > > ctx->scantable_type = -1; // set scantable type to uninitialized > memset(ctx->qmat_luma, 4, 64); > memset(ctx->qmat_chroma, 4, 64); > ctx->prev_slice_sf = 0; > > return 0; > } > > > /** > * Parse frame header. > */ > static int decode_frame_header(ProresContext * ctx, const uint8_t * buf, > const int data_size, AVCodecContext * avctx) > { > int hdr_size, version, width, height, flags; > const uint8_t *ptr; > > hdr_size = AV_RB16(buf); > if (hdr_size > data_size) { > av_log(avctx, AV_LOG_ERROR, "frame data too short!\n"); > return -1; > } > > version = AV_RB16(buf + 2); > if (version >= 2) { > av_log(avctx, AV_LOG_ERROR, "unsupported header version: %d\n", > version); > return -1; > } > > width = AV_RB16(buf + 8); > height = AV_RB16(buf + 10); > if (width != avctx->width || height != avctx->height) { > av_log(avctx, AV_LOG_ERROR, > "picture dimension changed! Old: %d x %d, new: %d x %d\n", > avctx->width, avctx->height, width, height); > return -1; > } > > ctx->frame_type = (buf[12] >> 2) & 3; > if (ctx->frame_type > 2) { > av_log(avctx, AV_LOG_ERROR, "unsupported frame type: %d!\n", > ctx->frame_type); > return -1; > } > > ctx->chroma_factor = (buf[12] >> 6) & 3; > ctx->mb_chroma_factor = ctx->chroma_factor + 2; > ctx->num_chroma_blocks = (1 << ctx->chroma_factor) >> 1; > switch (ctx->chroma_factor) { > case 2: > avctx->pix_fmt = PIX_FMT_YUV422P10; > break; > case 3: > avctx->pix_fmt = PIX_FMT_YUV444P10; > break; > default: > av_log(avctx, AV_LOG_ERROR, "unsupported picture format: %d!\n", > ctx->pic_format); > return -1; > } > > if (ctx->scantable_type != ctx->frame_type) { > if (!ctx->frame_type) > ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable, > progressive_scan); > else > ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable, > interlaced_scan); > ctx->scantable_type = ctx->frame_type; > } > > if (ctx->frame_type) { /* if interlaced */ > ctx->picture.interlaced_frame = 1; > ctx->picture.top_field_first = ctx->frame_type & 1; > } > > ctx->qmat_changed = 0; > ptr = buf + 20; > flags = buf[19]; > if (flags & 2) { > if (memcmp(ctx->qmat_luma, ptr, 64)) { > memcpy(ctx->qmat_luma, ptr, 64); > ctx->qmat_changed = 1; > } > ptr += 64; > } else { > memset(ctx->qmat_luma, 4, 64); > ctx->qmat_changed = 1; > } > > if (flags & 1) { > if (memcmp(ctx->qmat_chroma, ptr, 64)) { > memcpy(ctx->qmat_chroma, ptr, 64); > ctx->qmat_changed = 1; > } > } else { > memset(ctx->qmat_chroma, 4, 64); > ctx->qmat_changed = 1; > } > > return hdr_size; > } > > > /** > * Parse picture header. > */ > static int decode_picture_header(ProresContext * ctx, const uint8_t * buf, > const int data_size, AVCodecContext * avctx) > { > int i, hdr_size, pic_data_size, num_slices; > int slice_width_factor, slice_height_factor; > int remainder, num_x_slices; > const uint8_t *data_ptr, *index_ptr; > > hdr_size = data_size > 0 ? buf[0] >> 3 : 0; > if (hdr_size < 8 || hdr_size > data_size) { > av_log(avctx, AV_LOG_ERROR, "picture header too short!\n"); > return -1; > } > > pic_data_size = AV_RB32(buf + 1); > if (pic_data_size > data_size) { > av_log(avctx, AV_LOG_ERROR, "picture data too short!\n"); > return -1; > } > > slice_width_factor = buf[7] >> 4; > slice_height_factor = buf[7] & 0xF; > if (slice_width_factor > 3 || slice_height_factor) { > av_log(avctx, AV_LOG_ERROR, > "unsupported slice dimension: %d x %d!\n", > 1 << slice_width_factor, 1 << slice_height_factor); > return -1; > } > > ctx->slice_width_factor = slice_width_factor; > ctx->slice_height_factor = slice_height_factor; > > ctx->num_x_mbs = (avctx->width + 15) >> 4; > ctx->num_y_mbs = > (avctx->height + 15) >> (4 + ctx->picture.interlaced_frame); > > remainder = ctx->num_x_mbs & ((1 << slice_width_factor) - 1); > num_x_slices = (ctx->num_x_mbs >> slice_width_factor) + (remainder & 1) + > ((remainder >> 1) & 1) + ((remainder >> 2) & 1); > > num_slices = num_x_slices * ctx->num_y_mbs; > if (num_slices != AV_RB16(buf + 5)) { > av_log(avctx, AV_LOG_ERROR, "invalid number of slices!\n"); > return -1; > } > > if (ctx->total_slices != num_slices) { > av_freep(&ctx->slice_data_index); > ctx->slice_data_index = > av_malloc((num_slices + 1) * sizeof(uint8_t *)); > if (!ctx->slice_data_index) > return AVERROR(ENOMEM); > ctx->total_slices = num_slices; > } > > if (hdr_size + num_slices * 2 > data_size) { > av_log(avctx, AV_LOG_ERROR, "slice table too short!\n"); > return -1; > } > > /* parse slice table allowing quick access to the slice data */ > index_ptr = buf + hdr_size; > data_ptr = index_ptr + num_slices * 2; > > for (i = 0; i < num_slices; i++) { > ctx->slice_data_index[i] = data_ptr; > data_ptr += AV_RB16(index_ptr + i * 2); > } > ctx->slice_data_index[i] = data_ptr; > > if (data_ptr > buf + data_size) { > av_log(avctx, AV_LOG_ERROR, "out of slice data!\n"); > return -1; > } > > return pic_data_size; > } > > > /** > * Read an unsigned rice/exp golomb codeword. > */ > static inline int decode_vlc_codeword(GetBitContext * gb, uint8_t codebook) > { > unsigned int rice_order, exp_order, switch_bits; > unsigned int buf, code; > int log, prefix_len, len; > > OPEN_READER(re, gb); > UPDATE_CACHE(re, gb); > buf = GET_CACHE(re, gb); > > /* number of prefix bits to switch > between Rice and expGolomb */ > switch_bits = (codebook & 3) + 1; > rice_order = codebook >> 5; /* rice code order */ > exp_order = (codebook >> 2) & 7; /* exp golomb code order */ > > log = __builtin_clz(buf); /* count prefix bits (zeroes) */ please use standard av_log2() instead > if (log < switch_bits) { /* ok, we got a rice code */ > if (!rice_order) { > /* shortcut for faster decoding of rice codes without remainder */ > code = log; > LAST_SKIP_BITS(re, gb, log + 1); > } else { > prefix_len = log + 1; > code = (log << rice_order) + NEG_USR32((buf << prefix_len), > rice_order); > LAST_SKIP_BITS(re, gb, prefix_len + rice_order); > } > } else { /* otherwise we got a exp golomb code */ > len = (log << 1) - switch_bits + exp_order + 1; > code = NEG_USR32(buf, len) - (1 << exp_order) + > (switch_bits << rice_order); > LAST_SKIP_BITS(re, gb, len); > } > > CLOSE_READER(re, gb); > > return code; > } > > #define LSB2SIGN(x) (-((x) & 1)) > #define TOSIGNED(x) (((x) >> 1) ^ LSB2SIGN(x)) > > #define FIRST_DC_CB 0xB8 // rice_order = 5, exp_golomb_order = 6, switch_bits > = 0 > > static uint8_t dc_codebook[4] = { > 0x4, // rice_order = 0, exp_golomb_order = 1, switch_bits = 0 > 0x28, // rice_order = 1, exp_golomb_order = 2, switch_bits = 0 > 0x4D, // rice_order = 2, exp_golomb_order = 3, switch_bits = 1 > 0x70 // rice_order = 3, exp_golomb_order = 4, switch_bits = 0 > }; nit: 0x04 would look slightly better > /** > * Decode DC coefficients for all blocks in a slice. > */ > static inline void decode_dc_coeffs(GetBitContext * gb, DCTELEM *out, > int nblocks) > { > DCTELEM prev_dc; > int i, sign; > int16_t delta; > unsigned int code; > > code = decode_vlc_codeword(gb, FIRST_DC_CB); > out[0] = prev_dc = TOSIGNED(code); > > out += 64; /* move to the DC coeff of the next block */ > > delta = 3; > > for (i = 1; i < nblocks; i++, out += 64) { > code = decode_vlc_codeword(gb, dc_codebook[FFMIN(FFABS(delta), 3)]); > if (code < 0) > return; > > sign = -(((delta >> 15) & 1) ^ (code & 1)); > delta = (((code + 1) >> 1) ^ sign) - sign; > prev_dc += delta; > out[0] = prev_dc; > } > } > > > static uint8_t ac_codebook[7] = { > 0x4, // rice_order = 0, exp_golomb_order = 1, switch_bits = 0 > 0x28, // rice_order = 1, exp_golomb_order = 2, switch_bits = 0 > 0x4C, // rice_order = 2, exp_golomb_order = 3, switch_bits = 0 > 0x5, // rice_order = 0, exp_golomb_order = 1, switch_bits = 1 > 0x29, // rice_order = 1, exp_golomb_order = 2, switch_bits = 1 > 0x6, // rice_order = 0, exp_golomb_order = 1, switch_bits = 2 > 0xA, // rice_order = 0, exp_golomb_order = 2, switch_bits = 2 > }; > > /** > Lookup tables for adaptive switching between codebooks > according with previous run/level value. > */ > static uint8_t run_to_cb_index[16] = > { 5, 5, 3, 3, 0, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 2 }; > > static uint8_t lev_to_cb_index[10] = { 0, 6, 3, 5, 0, 1, 1, 1, 1, 2 }; > > > /** > * Decode AC coefficients for all blocks in a slice. > */ > static inline void decode_ac_coeffs(GetBitContext * gb, DCTELEM * out, > int blocks_per_slice, > int plane_size_factor, > const uint8_t * scan) > { > int pos, block_mask, run, level, sign, run_cb_index, lev_cb_index; > int max_coeffs, bits_left; > > /* set initial prediction values */ > run = 4; > level = 2; > max_coeffs = blocks_per_slice << 6; > block_mask = blocks_per_slice - 1; > > for (pos = blocks_per_slice - 1; pos < max_coeffs;) { > run_cb_index = run_to_cb_index[FFMIN(run, 15)]; > lev_cb_index = lev_to_cb_index[FFMIN(level, 9)]; > > bits_left = get_bits_left(gb); > if (bits_left <= 8 && !show_bits(gb, bits_left)) > return; > > run = decode_vlc_codeword(gb, ac_codebook[run_cb_index]); > > bits_left = get_bits_left(gb); > if (bits_left <= 8 && !show_bits(gb, bits_left)) > return; > > level = decode_vlc_codeword(gb, ac_codebook[lev_cb_index]) + 1; > > pos += run + 1; > if (pos >= max_coeffs) > break; > > sign = get_sbits(gb, 1); > out[((pos & block_mask) << 6) + scan[pos >> plane_size_factor]] = > (level ^ sign) - sign; > } > } > > > #define CLIP_AND_BIAS(x) (av_clip((x) + BIAS, CLIP_MIN, CLIP_MAX)) > > /** > * Add bias value, clamp and output pixels of a slice > */ > static void put_pixels(const DCTELEM * in, uint16_t * out, int stride, > int mbs_per_slice, int blocks_per_mb) > { > int mb, x, y, src_offset, dst_offset; > const DCTELEM *src1, *src2; > uint16_t *dst1, *dst2; > > src1 = in; > src2 = in + (blocks_per_mb << 5); > dst1 = out; > dst2 = out + (stride << 3); > > for (mb = 0; mb < mbs_per_slice; mb++) { > for (y = 0, dst_offset = 0; y < 8; y++, dst_offset += stride) { > for (x = 0; x < 8; x++) { > src_offset = (y << 3) + x; > > dst1[dst_offset + x] = CLIP_AND_BIAS(src1[src_offset]); > dst2[dst_offset + x] = CLIP_AND_BIAS(src2[src_offset]); > > if (blocks_per_mb > 2) { > dst1[dst_offset + x + 8] = > CLIP_AND_BIAS(src1[src_offset + 64]); > dst2[dst_offset + x + 8] = > CLIP_AND_BIAS(src2[src_offset + 64]); > } > } > } > > src1 += blocks_per_mb << 6; > src2 += blocks_per_mb << 6; > dst1 += blocks_per_mb << 2; > dst2 += blocks_per_mb << 2; > } > } why cannot you use put_pixels_clamped() or something similar? This looks like a perfect candidate for dsputil. > /** > * Decode a slice plane (luma or chroma). > */ > static void decode_slice_plane(ProresContext * ctx, const uint8_t * buf, > int data_size, uint16_t * out_ptr, > int linesize, int mbs_per_slice, > int blocks_per_mb, int plane_size_factor, > const int16_t * qmat) > { > GetBitContext gb; > DECLARE_ALIGNED(16, DCTELEM, blocks[8 * 4 * 64]); > DCTELEM *block_ptr; > int i, blk_num, blocks_per_slice; > > blocks_per_slice = mbs_per_slice * blocks_per_mb; > > memset(blocks, 0, sizeof(blocks)); > > init_get_bits(&gb, buf, data_size << 3); > > decode_dc_coeffs(&gb, blocks, blocks_per_slice); > > decode_ac_coeffs(&gb, blocks, blocks_per_slice, > plane_size_factor, ctx->scantable.permutated); > > /* inverse quantization, inverse transform and output */ > block_ptr = blocks; > > for (blk_num = 0; blk_num < blocks_per_slice; > blk_num++, block_ptr += 64) { > /* TODO: the correct solution shoud be (block_ptr[i] * qmat[i]) >> 1 > and the input of the inverse transform should be scaled by 2 > in order to avoid rounding errors. > Due to the fact the existing FFmpeg transforms are incompatible > with that > input I temporally introduced the coarse solution below... > */ > for (i = 0; i < 64; i++) > block_ptr[i] = (block_ptr[i] * qmat[i]) >> 2; > > ctx->dsp.idct(block_ptr); > } > > put_pixels(blocks, out_ptr, linesize >> 1, mbs_per_slice, > blocks_per_mb); > } > > > /** > * Decode a slice. > */ > static int decode_slice(ProresContext * ctx, int pic_num, int slice_num, > int mb_x_pos, int mb_y_pos, int mbs_per_slice, > AVCodecContext * avctx) > { > const uint8_t *buf; > uint8_t *y_data, *u_data, *v_data; > AVFrame *pic = avctx->coded_frame; > int i, sf, blocks_per_slice, slice_width_factor; > int slice_data_size, hdr_size, y_data_size, u_data_size, v_data_size; > int y_linesize, u_linesize, v_linesize; > > buf = ctx->slice_data_index[slice_num]; > slice_data_size = ctx->slice_data_index[slice_num + 1] - buf; > > slice_width_factor = av_log2(mbs_per_slice); > > y_data = pic->data[0]; > u_data = pic->data[1]; > v_data = pic->data[2]; > y_linesize = pic->linesize[0]; > u_linesize = pic->linesize[1]; > v_linesize = pic->linesize[2]; > > if (pic->interlaced_frame) { > if (!(pic_num ^ pic->top_field_first)) { > y_data += y_linesize; > u_data += u_linesize; > v_data += v_linesize; > } > y_linesize <<= 1; > u_linesize <<= 1; > v_linesize <<= 1; > } > > if (slice_data_size < 6) { > av_log(avctx, AV_LOG_ERROR, "slice data too short!\n"); > return -1; > } > > /* parse slice header */ > hdr_size = buf[0] >> 3; > y_data_size = AV_RB16(buf + 2); > u_data_size = AV_RB16(buf + 4); > v_data_size = slice_data_size - y_data_size - u_data_size - hdr_size; > > if (v_data_size < 0 || hdr_size < 6) { > av_log(avctx, AV_LOG_ERROR, "invalid data sizes!\n"); > return -1; > } > > sf = av_clip(buf[1], 1, 224); > sf = sf > 128 ? (sf - 96) << 2 : sf; > > /* scale quantization matrixes according with slice's scale factor */ > /* TODO: this can be SIMD-optimized alot */ > if (ctx->qmat_changed || sf != ctx->prev_slice_sf) { > ctx->prev_slice_sf = sf; > for (i = 0; i < 64; i++) { > ctx->qmat_luma_scaled[i] = ctx->qmat_luma[i] * sf; > ctx->qmat_chroma_scaled[i] = ctx->qmat_chroma[i] * sf; > } > } > > /* decode luma plane */ > decode_slice_plane(ctx, buf + hdr_size, y_data_size, > (uint16_t *) (y_data + (mb_y_pos << 4) * y_linesize + > (mb_x_pos << 5)), y_linesize, > mbs_per_slice, 4, slice_width_factor + 2, > ctx->qmat_luma_scaled); > > /* decode U chroma plane */ > decode_slice_plane(ctx, buf + hdr_size + y_data_size, u_data_size, > (uint16_t *) (u_data + (mb_y_pos << 4) * u_linesize + > (mb_x_pos << ctx->mb_chroma_factor)), > u_linesize, mbs_per_slice, ctx->num_chroma_blocks, > slice_width_factor + ctx->chroma_factor - 1, > ctx->qmat_chroma_scaled); > > /* decode V chroma plane */ > decode_slice_plane(ctx, buf + hdr_size + y_data_size + u_data_size, > v_data_size, > (uint16_t *) (v_data + (mb_y_pos << 4) * v_linesize + > (mb_x_pos << ctx->mb_chroma_factor)), > v_linesize, mbs_per_slice, ctx->num_chroma_blocks, > slice_width_factor + ctx->chroma_factor - 1, > ctx->qmat_chroma_scaled); > > return 0; > } > > > /** > * decode a picture > */ > static int decode_picture(ProresContext * ctx, int pic_num, > AVCodecContext * avctx) > { > int slice_num, slice_width, x_pos, y_pos; > > slice_num = 0; > > for (y_pos = 0; y_pos < ctx->num_y_mbs; y_pos++) { > slice_width = 1 << ctx->slice_width_factor; > > for (x_pos = 0; x_pos < ctx->num_x_mbs && slice_width; > x_pos += slice_width) { > while (ctx->num_x_mbs - x_pos < slice_width) > slice_width >>= 1; > > if (decode_slice > (ctx, pic_num, slice_num, x_pos, y_pos, slice_width, > avctx) < 0) > return -1; > > slice_num++; > } > } > > return 0; > } > > > #define FRAME_ID MKBETAG('i', 'c', 'p', 'f') > #define MOVE_DATA_PTR(nbytes) buf += (nbytes); buf_size -= (nbytes) > > /** > * main decoder function > */ > static int decode_frame(AVCodecContext * avctx, void *data, int *data_size, > AVPacket * avpkt) > { > ProresContext *ctx = avctx->priv_data; > AVFrame *picture = avctx->coded_frame; > const uint8_t *buf = avpkt->data; > int buf_size = avpkt->size; > int frame_hdr_size, pic_num, pic_data_size; > > /* check frame atom container */ > if (buf_size < 28 || buf_size < AV_RB32(buf) || > AV_RB32(buf + 4) != FRAME_ID) { > av_log(avctx, AV_LOG_ERROR, "invalid frame\n"); > return -1; > } > > MOVE_DATA_PTR(8); > > frame_hdr_size = decode_frame_header(ctx, buf, buf_size, avctx); > if (frame_hdr_size < 0) > return -1; > > MOVE_DATA_PTR(frame_hdr_size); > > if (picture->data[0]) > avctx->release_buffer(avctx, picture); > > picture->reference = 0; > if (avctx->get_buffer(avctx, picture) < 0) > return -1; > > for (pic_num = 0; ctx->picture.interlaced_frame - pic_num + 1; > pic_num++) { > pic_data_size = decode_picture_header(ctx, buf, buf_size, avctx); > if (pic_data_size < 0) > return -1; > > if (decode_picture(ctx, pic_num, avctx)) > return -1; > > MOVE_DATA_PTR(pic_data_size); > } > > *data_size = sizeof(AVPicture); > *(AVFrame *) data = *avctx->coded_frame; > > return avpkt->size; > } > > > /** > * Decoder close function. > */ > static av_cold int decode_close(AVCodecContext * avctx) > { > ProresContext *ctx = avctx->priv_data; > > if (ctx->picture.data[0]) > avctx->release_buffer(avctx, &ctx->picture); > > av_freep(&ctx->slice_data_index); > > return 0; > } > > > AVCodec ff_prores_decoder = { > .name = "ProRes", > .type = AVMEDIA_TYPE_VIDEO, > .id = CODEC_ID_PRORES, > .priv_data_size = sizeof(ProresContext), > .init = decode_init, > .close = decode_close, > .decode = decode_frame, > .capabilities = CODEC_CAP_DR1, > .long_name = NULL_IF_CONFIG_SMALL("Apple ProRes (iCodec Pro)") > }; > _______________________________________________ > libav-devel mailing list > [email protected] > https://lists.libav.org/mailman/listinfo/libav-devel _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
